From 1750895a65719282b7658f7963bc864d24522e73 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 01:24:48 +0200
Subject: [PATCH 01/19] removed simple_fail from ast_typed/misc.ml

---
 src/ast_typed/misc.ml | 128 ++++++++++++++++++++++++++++--------------
 src/typer/typer.ml    |  10 +++-
 2 files changed, 94 insertions(+), 44 deletions(-)

diff --git a/src/ast_typed/misc.ml b/src/ast_typed/misc.ml
index c1393fe53..1094815df 100644
--- a/src/ast_typed/misc.ml
+++ b/src/ast_typed/misc.ml
@@ -17,6 +17,11 @@ module Errors = struct
     let full () = Format.asprintf "%a VS %a" PP.type_value a PP.type_value b in
     error title full ()
 
+  let different_props_in_record ka kb () =
+    let title () = "different keys in record" in
+    let content () = Format.asprintf "%s vs %s" ka kb in
+    error title content ()
+
   let different_size_constants = different_size_type "constants"
 
   let different_size_tuples = different_size_type "tuples"
@@ -25,6 +30,50 @@ module Errors = struct
 
   let different_size_records = different_size_type "records"
 
+  let different_types name a b () =
+    let title () = name ^ " are different" in
+    let full () = Format.asprintf "%a VS %a" PP.type_value a PP.type_value b in
+    info title full ()
+
+  let different_literals name a b () =
+    let title () = name ^ " are different" in
+    let full () = Format.asprintf "%a VS %a" PP.literal a PP.literal b in
+    info title full ()
+
+  let different_values name a b () =
+    let title () = name ^ " are different" in
+    let full () = Format.asprintf "%a VS %a" PP.value a PP.value b in
+    info title full ()
+
+  let different_literals_because_different_types name a b () =
+    let title () = "literals have different types: " ^ name in
+    let full () = Format.asprintf "%a VS %a" PP.literal a PP.literal b in
+    info title full ()
+
+  let different_values_because_different_types name a b () =
+    let title () = "values have different types: " ^ name in
+    let full () = Format.asprintf "%a VS %a" PP.value a PP.value b in
+    info title full ()
+
+  let error_uncomparable_literals name a b () =
+    let title () = name ^ " are different" in
+    let full () = Format.asprintf "%a VS %a" PP.literal a PP.literal b in
+    info title full ()
+
+  let error_uncomparable_values name a b () =
+    let title () = name ^ " are different" in
+    let full () = Format.asprintf "%a VS %a" PP.value a PP.value b in
+    info title full ()
+
+  let different_size_values name a b () =
+    let title () = name in
+    let full () = Format.asprintf "%a VS %a" PP.value a PP.value b in
+    error title full ()
+
+  let missing_key_in_record_value k () =
+    let title () = "missing keys in one of the records" in
+    let content () = Format.asprintf "%s" k in
+    error title content ()
 end
 
 module Free_variables = struct
@@ -186,7 +235,7 @@ let rec assert_type_value_eq (a, b: (type_value * type_value)) : unit result = m
       let%bind _ =
         trace_strong (different_constants ca cb)
         @@ Assert.assert_true (ca = cb) in
-      trace (simple_error "constant sub-expression")
+      trace (different_types "constant sub-expression" a b)
       @@ bind_list_iter assert_type_value_eq (List.combine lsta lstb)
     )
   | T_constant _, _ -> fail @@ different_kinds a b
@@ -202,7 +251,7 @@ let rec assert_type_value_eq (a, b: (type_value * type_value)) : unit result = m
       let%bind _ =
         trace_strong (different_size_sums a b)
         @@ Assert.assert_list_same_size sa' sb' in
-      trace (simple_error "sum type") @@
+      trace (different_types "sum type" a b) @@
       bind_list_iter aux (List.combine sa' sb')
     )
   | T_sum _, _ -> fail @@ different_kinds a b
@@ -211,18 +260,15 @@ let rec assert_type_value_eq (a, b: (type_value * type_value)) : unit result = m
       let rb' = SMap.to_kv_list rb in
       let aux ((ka, va), (kb, vb)) =
         let%bind _ =
-          let error =
-            let title () = "different props in record" in
-            let content () = Format.asprintf "%s vs %s" ka kb in
-            error title content in
-          trace_strong error @@
+          trace (different_types "records" a b) @@
+          trace_strong (different_props_in_record ka kb) @@
           Assert.assert_true (ka = kb) in
         assert_type_value_eq (va, vb)
       in
       let%bind _ =
         trace_strong (different_size_records a b)
         @@ Assert.assert_list_same_size ra' rb' in
-      trace (simple_error "record type")
+      trace (different_types "record type" a b)
       @@ bind_list_iter aux (List.combine ra' rb')
 
     )
@@ -239,30 +285,30 @@ let type_value_eq ab = Trace.to_bool @@ assert_type_value_eq ab
 let assert_literal_eq (a, b : literal * literal) : unit result =
   match (a, b) with
   | Literal_bool a, Literal_bool b when a = b -> ok ()
-  | Literal_bool _, Literal_bool _ -> simple_fail "different bools"
-  | Literal_bool _, _ -> simple_fail "bool vs non-bool"
+  | Literal_bool _, Literal_bool _ -> fail @@ different_literals "booleans" a b
+  | Literal_bool _, _ -> fail @@ different_literals_because_different_types "bool vs non-bool" a b
   | Literal_int a, Literal_int b when a = b -> ok ()
-  | Literal_int _, Literal_int _ -> simple_fail "different ints"
-  | Literal_int _, _ -> simple_fail "int vs non-int"
+  | Literal_int _, Literal_int _ -> fail @@ different_literals "different ints" a b
+  | Literal_int _, _ -> fail @@ different_literals_because_different_types "int vs non-int" a b
   | Literal_nat a, Literal_nat b when a = b -> ok ()
-  | Literal_nat _, Literal_nat _ -> simple_fail "different nats"
-  | Literal_nat _, _ -> simple_fail "nat vs non-nat"
+  | Literal_nat _, Literal_nat _ -> fail @@ different_literals "different nats" a b
+  | Literal_nat _, _ -> fail @@ different_literals_because_different_types "nat vs non-nat" a b
   | Literal_tez a, Literal_tez b when a = b -> ok ()
-  | Literal_tez _, Literal_tez _ -> simple_fail "different tezs"
-  | Literal_tez _, _ -> simple_fail "tez vs non-tez"
+  | Literal_tez _, Literal_tez _ -> fail @@ different_literals "different tezs" a b
+  | Literal_tez _, _ -> fail @@ different_literals_because_different_types "tez vs non-tez" a b
   | Literal_string a, Literal_string b when a = b -> ok ()
-  | Literal_string _, Literal_string _ -> simple_fail "different strings"
-  | Literal_string _, _ -> simple_fail "string vs non-string"
+  | Literal_string _, Literal_string _ -> fail @@ different_literals "different strings" a b
+  | Literal_string _, _ -> fail @@ different_literals_because_different_types "string vs non-string" a b
   | Literal_bytes a, Literal_bytes b when a = b -> ok ()
-  | Literal_bytes _, Literal_bytes _ -> simple_fail "different bytess"
-  | Literal_bytes _, _ -> simple_fail "bytes vs non-bytes"
+  | Literal_bytes _, Literal_bytes _ -> fail @@ different_literals "different bytes" a b
+  | Literal_bytes _, _ -> fail @@ different_literals_because_different_types "bytes vs non-bytes" a b
   | Literal_unit, Literal_unit -> ok ()
-  | Literal_unit, _ -> simple_fail "unit vs non-unit"
+  | Literal_unit, _ -> fail @@ different_literals_because_different_types "unit vs non-unit" a b
   | Literal_address a, Literal_address b when a = b -> ok ()
-  | Literal_address _, Literal_address _ -> simple_fail "different addresss"
-  | Literal_address _, _ -> simple_fail "address vs non-address"
-  | Literal_operation _, Literal_operation _ -> simple_fail "can't compare operations"
-  | Literal_operation _, _ -> simple_fail "operation vs non-operation"
+  | Literal_address _, Literal_address _ -> fail @@ different_literals "different addresss" a b
+  | Literal_address _, _ -> fail @@ different_literals_because_different_types "address vs non-address" a b
+  | Literal_operation _, Literal_operation _ -> fail @@ error_uncomparable_literals "can't compare operations" a b
+  | Literal_operation _, _ -> fail @@ different_literals_because_different_types "operation vs non-operation" a b
 
 
 let rec assert_value_eq (a, b: (value*value)) : unit result =
@@ -275,13 +321,13 @@ let rec assert_value_eq (a, b: (value*value)) : unit result =
       assert_literal_eq (a, b)
   | E_constant (ca, lsta), E_constant (cb, lstb) when ca = cb -> (
       let%bind lst =
-        generic_try (simple_error "constants with different number of elements")
+        generic_try (different_size_values "constants with different number of elements" a b)
           (fun () -> List.combine lsta lstb) in
       let%bind _all = bind_list @@ List.map assert_value_eq lst in
       ok ()
     )
   | E_constant _, E_constant _ ->
-      simple_fail "different constants"
+      fail @@ different_values "constants" a b
   | E_constant _, _ ->
       let error_content () =
         Format.asprintf "%a vs %a"
@@ -295,34 +341,34 @@ let rec assert_value_eq (a, b: (value*value)) : unit result =
       ok ()
     )
   | E_constructor _, E_constructor _ ->
-      simple_fail "different constructors"
+      fail @@ different_values "constructors" a b
   | E_constructor _, _ ->
-      simple_fail "comparing constructor with other stuff"
+      fail @@ different_values_because_different_types "constructor vs. non-constructor" a b
 
   | E_tuple lsta, E_tuple lstb -> (
       let%bind lst =
-        generic_try (simple_error "tuples with different number of elements")
+        generic_try (different_size_values "tuples with different number of elements" a b)
           (fun () -> List.combine lsta lstb) in
       let%bind _all = bind_list @@ List.map assert_value_eq lst in
       ok ()
     )
   | E_tuple _, _ ->
-      simple_fail "comparing tuple with other stuff"
+      fail @@ different_values_because_different_types "tuple vs. non-tuple" a b
 
   | E_record sma, E_record smb -> (
-      let aux _ a b =
+      let aux k a b =
         match a, b with
         | Some a, Some b -> Some (assert_value_eq (a, b))
-        | _ -> Some (simple_fail "different record keys")
+        | _              -> Some (fail @@ missing_key_in_record_value k)
       in
       let%bind _all = bind_smap @@ SMap.merge aux sma smb in
       ok ()
     )
   | E_record _, _ ->
-      simple_fail "comparing record with other stuff"
+      fail @@ (different_values_because_different_types "record vs. non-record" a b)
 
   | E_map lsta, E_map lstb -> (
-      let%bind lst = generic_try (simple_error "maps of different lengths")
+      let%bind lst = generic_try (different_size_values "maps of different lengths" a b)
           (fun () ->
              let lsta' = List.sort compare lsta in
              let lstb' = List.sort compare lstb in
@@ -335,27 +381,27 @@ let rec assert_value_eq (a, b: (value*value)) : unit result =
       ok ()
     )
   | E_map _, _ ->
-      simple_fail "comparing map with other stuff"
+      fail @@ different_values_because_different_types "map vs. non-map" a b
 
   | E_list lsta, E_list lstb -> (
       let%bind lst =
-        generic_try (simple_error "list of different lengths")
+        generic_try (different_size_values "lists of different lengths" a b)
           (fun () -> List.combine lsta lstb) in
       let%bind _all = bind_map_list assert_value_eq lst in
       ok ()
     )
   | E_list _, _ ->
-      simple_fail "comparing list with other stuff"
+      fail @@ different_values_because_different_types "list vs. non-list" a b
   | (E_literal _, _) | (E_variable _, _) | (E_application _, _)
   | (E_lambda _, _) | (E_let_in _, _) | (E_tuple_accessor _, _)
   | (E_record_accessor _, _)
   | (E_look_up _, _) | (E_matching _, _) | (E_failwith _, _)
   | (E_assign _ , _)
-  | (E_sequence _, _) | (E_loop _, _)-> simple_fail "comparing not a value"
+  | (E_sequence _, _) | (E_loop _, _)-> fail @@ error_uncomparable_values "can't compare sequences nor loops" a b
 
-let merge_annotation (a:type_value option) (b:type_value option) : type_value result =
+let merge_annotation (a:type_value option) (b:type_value option) err : type_value result =
   match a, b with
-  | None, None -> simple_fail "no annotation"
+  | None, None -> fail @@ err
   | Some a, None -> ok a
   | None, Some b -> ok b
   | Some a, Some b ->
diff --git a/src/typer/typer.ml b/src/typer/typer.ml
index 1779837ce..61d2c8caf 100644
--- a/src/typer/typer.ml
+++ b/src/typer/typer.ml
@@ -504,7 +504,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
             @@ List.map fst lst' in
           let%bind annot = bind_map_option get_t_map_key tv_opt in
           trace (simple_info "empty map expression without a type annotation") @@
-          O.merge_annotation annot sub
+          O.merge_annotation annot sub (needs_annotation ae "this map literal")
         in
         let%bind value_type =
           let%bind sub =
@@ -513,7 +513,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
             @@ List.map snd lst' in
           let%bind annot = bind_map_option get_t_map_value tv_opt in
           trace (simple_info "empty map expression without a type annotation") @@
-          O.merge_annotation annot sub
+          O.merge_annotation annot sub (needs_annotation ae "this map literal")
         in
         ok (t_map key_type value_type ())
       in
@@ -710,7 +710,11 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
   | E_annotation (expr , te) ->
     let%bind tv = evaluate_type e te in
     let%bind expr' = type_expression ~tv_opt:tv e expr in
-    let%bind type_annotation = O.merge_annotation (Some tv) (Some expr'.type_annotation) in
+    let%bind type_annotation =
+      O.merge_annotation
+        (Some tv)
+        (Some expr'.type_annotation)
+        (simple_error "assertion failed") in
     ok {expr' with type_annotation}
 
 

From 24db060dae71644a6b9fc26b7f376c8a2bfcf782 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 11:38:59 +0200
Subject: [PATCH 02/19] Use internal_assertion_fail instead of the simple_error
 that are just assertions

---
 src/transpiler/transpiler.ml             | 6 +++---
 src/typer/typer.ml                       | 4 ++--
 vendors/ligo-utils/simple-utils/trace.ml | 1 +
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/src/transpiler/transpiler.ml b/src/transpiler/transpiler.ml
index 7da6985e9..47582e004 100644
--- a/src/transpiler/transpiler.ml
+++ b/src/transpiler/transpiler.ml
@@ -603,7 +603,7 @@ let extract_constructor (v : value) (tree : _ Append_tree.t') : (string * value
     | Leaf (k, t), v -> ok (k, v, t)
     | Node {a}, D_left v -> aux (a, v)
     | Node {b}, D_right v -> aux (b, v)
-    | _ -> simple_fail "bad constructor path"
+    | _ -> internal_assertion_fail "bad constructor path"
   in
   let%bind (s, v, t) = aux (tree, v) in
   ok (s, v, t)
@@ -617,7 +617,7 @@ let extract_tuple (v : value) (tree : AST.type_value Append_tree.t') : ((value *
         let%bind a' = aux (a, va) in
         let%bind b' = aux (b, vb) in
         ok (a' @ b')
-    | _ -> simple_fail "bad tuple path"
+    | _ -> internal_assertion_fail "bad tuple path"
   in
   aux (tree, v)
 
@@ -630,7 +630,7 @@ let extract_record (v : value) (tree : _ Append_tree.t') : (_ list) result =
         let%bind a' = aux (a, va) in
         let%bind b' = aux (b, vb) in
         ok (a' @ b')
-    | _ -> simple_fail "bad record path"
+    | _ -> internal_assertion_fail "bad record path"
   in
   aux (tree, v)
 
diff --git a/src/typer/typer.ml b/src/typer/typer.ml
index 61d2c8caf..643196e79 100644
--- a/src/typer/typer.ml
+++ b/src/typer/typer.ml
@@ -714,7 +714,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
       O.merge_annotation
         (Some tv)
         (Some expr'.type_annotation)
-        (simple_error "assertion failed") in
+        (internal_assertion_fail "merge_annotations (Some ...) (Some ...) failed") in
     ok {expr' with type_annotation}
 
 
@@ -729,7 +729,7 @@ and type_constant (name:string) (lst:O.type_value list) (tv_opt:O.type_value opt
 let untype_type_value (t:O.type_value) : (I.type_expression) result =
   match t.simplified with
   | Some s -> ok s
-  | _ -> simple_fail "trying to untype generated type"
+  | _ -> internal_assertion_fail "trying to untype generated type"
 
 let untype_literal (l:O.literal) : I.literal result =
   let open I in
diff --git a/vendors/ligo-utils/simple-utils/trace.ml b/vendors/ligo-utils/simple-utils/trace.ml
index c175b4149..4669f07a1 100644
--- a/vendors/ligo-utils/simple-utils/trace.ml
+++ b/vendors/ligo-utils/simple-utils/trace.ml
@@ -200,6 +200,7 @@ let prepend_info = fun info err ->
 let simple_error str () = mk_error ~title:(thunk str) ()
 let simple_info str () = mk_info ~title:(thunk str) ()
 let simple_fail str = fail @@ simple_error str
+let internal_assertion_fail str = fail @@ simple_error ("assertion failed: " ^ str)
 
 (**
    To be used when you only want to signal an error. It can be useful when

From 64e848b2de171b3ac7f67eb86edab6b556038d61 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 11:48:33 +0200
Subject: [PATCH 03/19] structured errors for ast_typed/misc.ml

---
 src/ast_typed/misc.ml | 103 +++++++++++++++++++++++++++++++-----------
 1 file changed, 77 insertions(+), 26 deletions(-)

diff --git a/src/ast_typed/misc.ml b/src/ast_typed/misc.ml
index 1094815df..53b03c2be 100644
--- a/src/ast_typed/misc.ml
+++ b/src/ast_typed/misc.ml
@@ -4,23 +4,39 @@ open Types
 module Errors = struct
   let different_kinds a b () =
     let title = (thunk "different kinds") in
-    let full () = Format.asprintf "(%a) VS (%a)" PP.type_value a PP.type_value b in
-    error title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.type_value a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.type_value b )
+    ] in
+    error ~data title message ()
 
   let different_constants a b () =
     let title = (thunk "different constants") in
-    let full () = Format.asprintf "%s VS %s" a b in
-    error title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%s)" a) ;
+      ("b" , fun () -> Format.asprintf "(%s)" b )
+    ] in
+    error ~data title message ()
 
   let different_size_type name a b () =
     let title () = name ^ " have different sizes" in
-    let full () = Format.asprintf "%a VS %a" PP.type_value a PP.type_value b in
-    error title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.type_value a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.type_value b )
+    ] in
+    error ~data title message ()
 
   let different_props_in_record ka kb () =
     let title () = "different keys in record" in
-    let content () = Format.asprintf "%s vs %s" ka kb in
-    error title content ()
+    let message () = "" in
+    let data = [
+      ("key_a" , fun () -> Format.asprintf "(%s)" ka) ;
+      ("key_b" , fun () -> Format.asprintf "(%s)" kb )
+    ] in
+    error ~data title message ()
 
   let different_size_constants = different_size_type "constants"
 
@@ -32,48 +48,83 @@ module Errors = struct
 
   let different_types name a b () =
     let title () = name ^ " are different" in
-    let full () = Format.asprintf "%a VS %a" PP.type_value a PP.type_value b in
-    info title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.type_value a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.type_value b )
+    ] in
+    error ~data title message ()
 
   let different_literals name a b () =
     let title () = name ^ " are different" in
-    let full () = Format.asprintf "%a VS %a" PP.literal a PP.literal b in
-    info title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.literal a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.literal b )
+    ] in
+    error ~data title message ()
 
   let different_values name a b () =
     let title () = name ^ " are different" in
-    let full () = Format.asprintf "%a VS %a" PP.value a PP.value b in
-    info title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.value a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.value b )
+    ] in
+    error ~data title message ()
 
   let different_literals_because_different_types name a b () =
     let title () = "literals have different types: " ^ name in
-    let full () = Format.asprintf "%a VS %a" PP.literal a PP.literal b in
-    info title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.literal a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.literal b )
+    ] in
+    error ~data title message ()
 
   let different_values_because_different_types name a b () =
     let title () = "values have different types: " ^ name in
-    let full () = Format.asprintf "%a VS %a" PP.value a PP.value b in
-    info title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.value a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.value b )
+    ] in
+    error ~data title message ()
 
   let error_uncomparable_literals name a b () =
     let title () = name ^ " are different" in
-    let full () = Format.asprintf "%a VS %a" PP.literal a PP.literal b in
-    info title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.literal a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.literal b )
+    ] in
+    error ~data title message ()
 
   let error_uncomparable_values name a b () =
     let title () = name ^ " are different" in
-    let full () = Format.asprintf "%a VS %a" PP.value a PP.value b in
-    info title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.value a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.value b )
+    ] in
+    error ~data title message ()
 
   let different_size_values name a b () =
     let title () = name in
-    let full () = Format.asprintf "%a VS %a" PP.value a PP.value b in
-    error title full ()
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "(%a)" PP.value a) ;
+      ("b" , fun () -> Format.asprintf "(%a)" PP.value b )
+    ] in
+    error ~data title message ()
 
   let missing_key_in_record_value k () =
     let title () = "missing keys in one of the records" in
-    let content () = Format.asprintf "%s" k in
-    error title content ()
+    let message () = "" in
+    let data = [
+      ("missing_key" , fun () -> Format.asprintf "%s" k)
+    ] in
+    error ~data title message ()
 end
 
 module Free_variables = struct

From e0228f352ce59120b934dde9fd75950cb6f5b3ce Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 14:26:01 +0200
Subject: [PATCH 04/19] fix build (my bad)

---
 src/transpiler/transpiler.ml             | 6 +++---
 src/typer/typer.ml                       | 4 ++--
 vendors/ligo-utils/simple-utils/trace.ml | 2 +-
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/transpiler/transpiler.ml b/src/transpiler/transpiler.ml
index 47582e004..4b27b2dcc 100644
--- a/src/transpiler/transpiler.ml
+++ b/src/transpiler/transpiler.ml
@@ -603,7 +603,7 @@ let extract_constructor (v : value) (tree : _ Append_tree.t') : (string * value
     | Leaf (k, t), v -> ok (k, v, t)
     | Node {a}, D_left v -> aux (a, v)
     | Node {b}, D_right v -> aux (b, v)
-    | _ -> internal_assertion_fail "bad constructor path"
+    | _ -> fail @@ internal_assertion_failure "bad constructor path"
   in
   let%bind (s, v, t) = aux (tree, v) in
   ok (s, v, t)
@@ -617,7 +617,7 @@ let extract_tuple (v : value) (tree : AST.type_value Append_tree.t') : ((value *
         let%bind a' = aux (a, va) in
         let%bind b' = aux (b, vb) in
         ok (a' @ b')
-    | _ -> internal_assertion_fail "bad tuple path"
+    | _ -> fail @@ internal_assertion_failure "bad tuple path"
   in
   aux (tree, v)
 
@@ -630,7 +630,7 @@ let extract_record (v : value) (tree : _ Append_tree.t') : (_ list) result =
         let%bind a' = aux (a, va) in
         let%bind b' = aux (b, vb) in
         ok (a' @ b')
-    | _ -> internal_assertion_fail "bad record path"
+    | _ -> fail @@ internal_assertion_failure "bad record path"
   in
   aux (tree, v)
 
diff --git a/src/typer/typer.ml b/src/typer/typer.ml
index 643196e79..0f4c6d0a9 100644
--- a/src/typer/typer.ml
+++ b/src/typer/typer.ml
@@ -714,7 +714,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
       O.merge_annotation
         (Some tv)
         (Some expr'.type_annotation)
-        (internal_assertion_fail "merge_annotations (Some ...) (Some ...) failed") in
+        (internal_assertion_failure "merge_annotations (Some ...) (Some ...) failed") in
     ok {expr' with type_annotation}
 
 
@@ -729,7 +729,7 @@ and type_constant (name:string) (lst:O.type_value list) (tv_opt:O.type_value opt
 let untype_type_value (t:O.type_value) : (I.type_expression) result =
   match t.simplified with
   | Some s -> ok s
-  | _ -> internal_assertion_fail "trying to untype generated type"
+  | _ -> fail @@ internal_assertion_failure "trying to untype generated type"
 
 let untype_literal (l:O.literal) : I.literal result =
   let open I in
diff --git a/vendors/ligo-utils/simple-utils/trace.ml b/vendors/ligo-utils/simple-utils/trace.ml
index 4669f07a1..582347eae 100644
--- a/vendors/ligo-utils/simple-utils/trace.ml
+++ b/vendors/ligo-utils/simple-utils/trace.ml
@@ -200,7 +200,7 @@ let prepend_info = fun info err ->
 let simple_error str () = mk_error ~title:(thunk str) ()
 let simple_info str () = mk_info ~title:(thunk str) ()
 let simple_fail str = fail @@ simple_error str
-let internal_assertion_fail str = fail @@ simple_error ("assertion failed: " ^ str)
+let internal_assertion_failure str = simple_error ("assertion failed: " ^ str)
 
 (**
    To be used when you only want to signal an error. It can be useful when

From 0e01353c7d739d2cdf858dad51deff492493a917 Mon Sep 17 00:00:00 2001
From: Christian Rinderknecht <Christian.Rinderknecht@tezcore.com>
Date: Wed, 5 Jun 2019 17:51:06 +0200
Subject: [PATCH 05/19] Finished upgrading the error reporting for Pascaligo.

---
 src/simplify/pascaligo.ml | 258 ++++++++++++++++++++++++++++++++------
 1 file changed, 217 insertions(+), 41 deletions(-)

diff --git a/src/simplify/pascaligo.ml b/src/simplify/pascaligo.ml
index cc5a027f9..6925d2ba5 100644
--- a/src/simplify/pascaligo.ml
+++ b/src/simplify/pascaligo.ml
@@ -15,10 +15,21 @@ let pseq_to_list = function
 let get_value : 'a Raw.reg -> 'a = fun x -> x.value
 
 module Errors = struct
+  let unsupported_ass_None region =
+    let title () = "assignment of None" in
+    let message () =
+      Format.asprintf "assignments of None are not supported yet" in
+    let data = [
+      ("none_expr",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ region)
+    ] in
+    error ~data title message
+
   let unsupported_entry_decl decl =
     let title () = "entry point declarations" in
     let message () =
-      Format.asprintf "entry points within the contract are not supported yet" in
+      Format.asprintf "entry points within the contract \
+                       are not supported yet" in
     let data = [
       ("declaration",
        fun () -> Format.asprintf "%a" Location.pp_lift @@ decl.Region.region)
@@ -92,13 +103,176 @@ module Errors = struct
   let unsupported_set_expr expr =
     let title () = "set expressions" in
     let message () =
-      Format.asprintf "set type is not supported yet" in
+      Format.asprintf "the set type is not supported yet" in
      let expr_loc = Raw.expr_to_region expr in
     let data = [
       ("expr_loc",
        fun () -> Format.asprintf "%a" Location.pp_lift @@ expr_loc)
     ] in
     error ~data title message
+
+  let unsupported_proc_calls call =
+    let title () = "procedure calls" in
+    let message () =
+      Format.asprintf "procedure calls are not supported yet" in
+    let data = [
+      ("call_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ call.Region.region)
+    ] in
+    error ~data title message
+
+  let unsupported_for_loops region =
+    let title () = "bounded iterators" in
+    let message () =
+      Format.asprintf "for loops are not supported yet" in
+    let data = [
+      ("loop_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ region)
+    ] in
+    error ~data title message
+
+  let unsupported_deep_map_assign v =
+    let title () = "map assignments" in
+    let message () =
+      Format.asprintf "assignments to embedded maps are not \
+                       supported yet" in
+    let data = [
+      ("lhs_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ v.Region.region)
+    ] in
+    error ~data title message
+
+  let unsupported_empty_record_patch record_expr =
+    let title () = "empty record patch" in
+    let message () =
+      Format.asprintf "empty record patches are not supported yet" in
+    let data = [
+      ("record_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ record_expr.Region.region)
+    ] in
+    error ~data title message
+
+  let unsupported_map_patches patch =
+    let title () = "map patches" in
+    let message () =
+      Format.asprintf "map patches (a.k.a. functional updates) are \
+                       not supported yet" in
+    let data = [
+      ("patch_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ patch.Region.region)
+    ] in
+    error ~data title message
+
+  let unsupported_set_patches patch =
+    let title () = "set patches" in
+    let message () =
+      Format.asprintf "set patches (a.k.a. functional updates) are \
+                       not supported yet" in
+    let data = [
+      ("patch_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ patch.Region.region)
+    ] in
+    error ~data title message
+
+  let unsupported_deep_map_rm path =
+    let title () = "binding removals" in
+    let message () =
+      Format.asprintf "removal of bindings from embedded maps \
+                       are not supported yet" in
+    let data = [
+      ("path_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ path.Region.region)
+    ] in
+    error ~data title message
+
+  let unsupported_set_removal remove =
+    let title () = "set removals" in
+    let message () =
+      Format.asprintf "removal of elements in a set is not \
+                       supported yet" in
+    let data = [
+      ("removal_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ remove.Region.region)
+    ] in
+    error ~data title message
+
+  let unsupported_non_var_pattern p =
+    let title () = "pattern is not a variable" in
+    let message () =
+      Format.asprintf "non-variable patterns in constructors \
+                       are not supported yet" in
+    let pattern_loc = Raw.pattern_to_region p in
+    let data = [
+      ("pattern_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ pattern_loc)
+    ] in
+    error ~data title message
+
+  let only_constructors p =
+    let title () = "constructors in patterns" in
+    let message () =
+      Format.asprintf "currently, only constructors are supported in patterns" in
+    let pattern_loc = Raw.pattern_to_region p in
+    let data = [
+      ("pattern_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ pattern_loc)
+    ] in
+    error ~data title message
+
+  let unsupported_tuple_pattern p =
+    let title () = "tuple pattern" in
+    let message () =
+      Format.asprintf "tuple patterns are not supported yet" in
+    let pattern_loc = Raw.pattern_to_region p in
+    let data = [
+      ("pattern_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ pattern_loc)
+    ] in
+    error ~data title message
+
+  let unsupported_deep_Some_patterns pattern =
+    let title () = "option patterns" in
+    let message () =
+      Format.asprintf "currently, only variables in Some constructors \
+                       in patterns are supported" in
+    let pattern_loc = Raw.pattern_to_region pattern in
+    let data = [
+      ("pattern_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ pattern_loc)
+    ] in
+    error ~data title message
+
+  let unsupported_deep_list_patterns cons =
+    let title () = "lists in patterns" in
+    let message () =
+      Format.asprintf "currently, only empty lists and x::y \
+                       are supported in patterns" in
+    let data = [
+      ("pattern_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ cons.Region.region)
+    ] in
+    error ~data title message
+
+  let unsupported_sub_blocks b =
+    let title () = "block instructions" in
+    let message () =
+      Format.asprintf "Sub-blocks are not supported yet" in
+    let data = [
+      ("block_loc",
+       fun () -> Format.asprintf "%a" Location.pp_lift @@ b.Region.region)
+    ] in
+    error ~data title message
+
+  (* Logging *)
+
+  let simplifying_instruction t =
+    let title () = "simplifiying instruction" in
+    let message () = "" in
+    let data = [
+      ("instruction",
+       fun () -> Format.asprintf "%a" PP_helpers.(printer Parser.Pascaligo.ParserLog.print_instruction) t)
+    ] in
+    error ~data title message
 end
 
 open Errors
@@ -542,7 +716,8 @@ and simpl_statement : Raw.statement -> (_ -> expression result) result =
 and simpl_single_instruction : Raw.single_instr -> (_ -> expression result) result =
   fun t ->
   match t with
-  | ProcCall _ -> simple_fail "no proc call"
+  | ProcCall call ->
+      fail @@ unsupported_proc_calls call
   | Fail e -> (
       let%bind expr = simpl_expression e.value.fail_expr in
       return @@ e_failwith expr
@@ -557,8 +732,8 @@ and simpl_single_instruction : Raw.single_instr -> (_ -> expression result) resu
       let%bind body = simpl_block l.block.value in
       let%bind body = body None in
       return @@ e_loop cond body
-  | Loop (For _) ->
-      simple_fail "no for yet"
+  | Loop (For (ForInt {region; _} | ForCollect {region; _})) ->
+      fail @@ unsupported_for_loops region
   | Cond c -> (
       let (c , loc) = r_split c in
       let%bind expr = simpl_expression c.test in
@@ -576,7 +751,7 @@ and simpl_single_instruction : Raw.single_instr -> (_ -> expression result) resu
       let (a , loc) = r_split a in
       let%bind value_expr = match a.rhs with
         | Expr e -> simpl_expression e
-        | NoneExpr _ -> simple_fail "no none assignments yet"
+        | NoneExpr reg -> fail @@ unsupported_ass_None reg
       in
       match a.lhs with
         | Path path -> (
@@ -587,7 +762,7 @@ and simpl_single_instruction : Raw.single_instr -> (_ -> expression result) resu
             let v' = v.value in
             let%bind name = match v'.path with
               | Name name -> ok name
-              | _ -> simple_fail "no complex map assignments yet" in
+              | _ -> fail @@ unsupported_deep_map_assign v in
             let%bind key_expr = simpl_expression v'.index.value.inside in
             let old_expr = e_variable name.value in
             let expr' = e_map_update key_expr value_expr old_expr in
@@ -614,7 +789,8 @@ and simpl_single_instruction : Raw.single_instr -> (_ -> expression result) resu
       let%bind inj = bind_list
         @@ List.map (fun (x:Raw.field_assign Region.reg) ->
             let (x , loc) = r_split x in
-            let%bind e = simpl_expression x.field_expr in ok (x.field_name.value, e , loc)
+            let%bind e = simpl_expression x.field_expr
+            in ok (x.field_name.value, e , loc)
           )
         @@ pseq_to_list r.record_inj.value.elements in
       let%bind expr =
@@ -622,27 +798,30 @@ and simpl_single_instruction : Raw.single_instr -> (_ -> expression result) resu
           e_assign ~loc name (access_path @ [ Access_record access ]) v in
         let assigns = List.map aux inj in
         match assigns with
-        | [] -> simple_fail "empty record patch"
+               (* E_sequence (E_skip, E_skip) ? *)
+        | [] -> fail @@ unsupported_empty_record_patch r.record_inj
         | hd :: tl -> (
-            let aux acc cur = e_sequence (acc) (cur) in
+            let aux acc cur = e_sequence acc cur in
             ok @@ List.fold_left aux hd tl
           )
       in
       return @@ expr
     )
-  | MapPatch _ -> simple_fail "no map patch yet"
-  | SetPatch _ -> simple_fail "no set patch yet"
+  | MapPatch patch ->
+      fail @@ unsupported_map_patches patch
+  | SetPatch patch ->
+      fail @@ unsupported_set_patches patch
   | MapRemove r -> (
       let (v , loc) = r_split r in
       let key = v.key in
       let%bind map = match v.map with
         | Name v -> ok v.value
-        | _ -> simple_fail "no complex map remove yet" in
+        | Path path -> fail @@ unsupported_deep_map_rm path in
       let%bind key' = simpl_expression key in
       let expr = e_constant ~loc "MAP_REMOVE" [key' ; e_variable map] in
       return @@ e_assign ~loc map [] expr
     )
-  | SetRemove _ -> simple_fail "no set remove yet"
+  | SetRemove r -> fail @@ unsupported_set_removal r
 
 and simpl_path : Raw.path -> string * Ast_simplified.access_path = fun p ->
   match p with
@@ -663,15 +842,10 @@ and simpl_path : Raw.path -> string * Ast_simplified.access_path = fun p ->
 
 and simpl_cases : type a . (Raw.pattern * a) list -> a matching result = fun t ->
   let open Raw in
-  let get_var (t:Raw.pattern) = match t with
+  let get_var (t:Raw.pattern) =
+    match t with
     | PVar v -> ok v.value
-    | _ ->
-        let error =
-          let title () = "not a var" in
-          let content () = Format.asprintf "%a" (PP_helpers.printer Parser.Pascaligo.ParserLog.print_pattern) t in
-          error title content
-        in
-        fail error
+    | p -> fail @@ unsupported_non_var_pattern p
   in
   let get_tuple (t:Raw.pattern) = match t with
     | PCons v -> npseq_to_list v.value
@@ -681,32 +855,33 @@ and simpl_cases : type a . (Raw.pattern * a) list -> a matching result = fun t -
   let get_single (t:Raw.pattern) =
     let t' = get_tuple t in
     let%bind () =
-      trace_strong (simple_error "not single") @@
+      trace_strong (unsupported_tuple_pattern t) @@
       Assert.assert_list_size t' 1 in
     ok (List.hd t') in
   let get_constr (t:Raw.pattern) = match t with
     | PConstr v ->
         let%bind var = get_single (snd v.value).value >>? get_var in
         ok ((fst v.value).value , var)
-    | _ -> simple_fail "not a constr"
+    | _ -> fail @@ only_constructors t
   in
   let%bind patterns =
     let aux (x , y) =
       let xs = get_tuple x in
-      trace_strong (simple_error "no tuple in patterns yet") @@
+      trace_strong (unsupported_tuple_pattern x) @@
       Assert.assert_list_size xs 1 >>? fun () ->
       ok (List.hd xs , y)
     in
     bind_map_list aux t in
   match patterns with
   | [(PFalse _ , f) ; (PTrue _ , t)]
-  | [(PTrue _ , t) ; (PFalse _ , f)] -> ok @@ Match_bool {match_true = t ; match_false = f}
+  | [(PTrue _ , t) ; (PFalse _ , f)] ->
+      ok @@ Match_bool {match_true = t ; match_false = f}
   | [(PSome v , some) ; (PNone _ , none)]
   | [(PNone _ , none) ; (PSome v , some)] -> (
       let (_, v) = v.value in
       let%bind v = match v.value.inside with
         | PVar v -> ok v.value
-        | _ -> simple_fail "complex none patterns not supported yet" in
+        | p -> fail @@ unsupported_deep_Some_patterns p in
       ok @@ Match_option {match_none = none ; match_some = (v, some) }
     )
   | [(PCons c , cons) ; (PList (PNil _) , nil)]
@@ -717,11 +892,12 @@ and simpl_cases : type a . (Raw.pattern * a) list -> a matching result = fun t -
             let%bind a = get_var a in
             let%bind b = get_var b in
             ok (a, b)
-        | _ -> simple_fail "complex list patterns not supported yet"
+        | _ -> fail @@ unsupported_deep_list_patterns c
       in
       ok @@ Match_list {match_cons = (a, b, cons) ; match_nil = nil}
   | lst ->
-      trace (simple_error "weird patterns not supported yet") @@
+      trace (simple_info "currently, only booleans, options, lists and \
+                         user-defined constructors are supported in patterns") @@
       let%bind constrs =
         let aux (x , y) =
           let error =
@@ -736,27 +912,27 @@ and simpl_cases : type a . (Raw.pattern * a) list -> a matching result = fun t -
         bind_map_list aux lst in
       ok @@ Match_variant constrs
 
-and simpl_instruction_block : Raw.instruction -> (_ -> expression result) result = fun t ->
+and simpl_instruction_block : Raw.instruction -> (_ -> expression result) result =
+  fun t ->
   match t with
   | Single s -> simpl_single_instruction s
   | Block b -> simpl_block b.value
 
-and simpl_instruction : Raw.instruction -> (_ -> expression result) result = fun t ->
-  let main_error =
-    let title () = "simplifiying instruction" in
-    let content () = Format.asprintf "%a" PP_helpers.(printer Parser.Pascaligo.ParserLog.print_instruction) t in
-    error title content in
-  trace main_error @@
+and simpl_instruction : Raw.instruction -> (_ -> expression result) result =
+  fun t ->
+  trace (simplifying_instruction t) @@
   match t with
   | Single s -> simpl_single_instruction s
-  | Block _ -> simple_fail "no block instruction yet"
+  | Block b -> fail @@ unsupported_sub_blocks b
 
-and simpl_statements : Raw.statements -> (_ -> expression result) result = fun ss ->
+and simpl_statements : Raw.statements -> (_ -> expression result) result =
+  fun ss ->
   let lst = npseq_to_list ss in
   let%bind fs = bind_map_list simpl_statement lst in
-  let aux : _ -> (expression option -> expression result) -> _ = fun prec cur ->
-    let%bind res = cur prec in
-    ok @@ Some res in
+  let aux : _ -> (expression option -> expression result) -> _ =
+    fun prec cur ->
+      let%bind res = cur prec in
+      ok @@ Some res in
   ok @@ fun (expr' : _ option) ->
   let%bind ret = bind_fold_right_list aux expr' fs in
   ok @@ Option.unopt_exn ret

From 347774e42baf7d6207ea6bebfd1921d078f2776b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 19:16:54 +0200
Subject: [PATCH 06/19] Improved error messages

---
 src/ast_typed/misc.ml    | 52 ++++++++++++++++++++--------------------
 src/bin/cli.ml           |  2 +-
 src/operators/helpers.ml | 23 ++++++++++++------
 3 files changed, 43 insertions(+), 34 deletions(-)

diff --git a/src/ast_typed/misc.ml b/src/ast_typed/misc.ml
index 53b03c2be..077f00c0a 100644
--- a/src/ast_typed/misc.ml
+++ b/src/ast_typed/misc.ml
@@ -6,8 +6,8 @@ module Errors = struct
     let title = (thunk "different kinds") in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.type_value a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.type_value b )
+      ("a" , fun () -> Format.asprintf "%a" PP.type_value a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.type_value b )
     ] in
     error ~data title message ()
 
@@ -15,8 +15,8 @@ module Errors = struct
     let title = (thunk "different constants") in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%s)" a) ;
-      ("b" , fun () -> Format.asprintf "(%s)" b )
+      ("a" , fun () -> Format.asprintf "%s" a) ;
+      ("b" , fun () -> Format.asprintf "%s" b )
     ] in
     error ~data title message ()
 
@@ -24,8 +24,8 @@ module Errors = struct
     let title () = name ^ " have different sizes" in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.type_value a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.type_value b )
+      ("a" , fun () -> Format.asprintf "%a" PP.type_value a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.type_value b )
     ] in
     error ~data title message ()
 
@@ -33,8 +33,8 @@ module Errors = struct
     let title () = "different keys in record" in
     let message () = "" in
     let data = [
-      ("key_a" , fun () -> Format.asprintf "(%s)" ka) ;
-      ("key_b" , fun () -> Format.asprintf "(%s)" kb )
+      ("key_a" , fun () -> Format.asprintf "%s" ka) ;
+      ("key_b" , fun () -> Format.asprintf "%s" kb )
     ] in
     error ~data title message ()
 
@@ -50,8 +50,8 @@ module Errors = struct
     let title () = name ^ " are different" in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.type_value a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.type_value b )
+      ("a" , fun () -> Format.asprintf "%a" PP.type_value a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.type_value b )
     ] in
     error ~data title message ()
 
@@ -59,8 +59,8 @@ module Errors = struct
     let title () = name ^ " are different" in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.literal a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.literal b )
+      ("a" , fun () -> Format.asprintf "%a" PP.literal a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.literal b )
     ] in
     error ~data title message ()
 
@@ -68,8 +68,8 @@ module Errors = struct
     let title () = name ^ " are different" in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.value a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.value b )
+      ("a" , fun () -> Format.asprintf "%a" PP.value a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.value b )
     ] in
     error ~data title message ()
 
@@ -77,8 +77,8 @@ module Errors = struct
     let title () = "literals have different types: " ^ name in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.literal a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.literal b )
+      ("a" , fun () -> Format.asprintf "%a" PP.literal a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.literal b )
     ] in
     error ~data title message ()
 
@@ -86,26 +86,26 @@ module Errors = struct
     let title () = "values have different types: " ^ name in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.value a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.value b )
+      ("a" , fun () -> Format.asprintf "%a" PP.value a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.value b )
     ] in
     error ~data title message ()
 
   let error_uncomparable_literals name a b () =
-    let title () = name ^ " are different" in
+    let title () = name ^ " are not comparable" in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.literal a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.literal b )
+      ("a" , fun () -> Format.asprintf "%a" PP.literal a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.literal b )
     ] in
     error ~data title message ()
 
   let error_uncomparable_values name a b () =
-    let title () = name ^ " are different" in
+    let title () = name ^ " are not comparable" in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.value a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.value b )
+      ("a" , fun () -> Format.asprintf "%a" PP.value a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.value b )
     ] in
     error ~data title message ()
 
@@ -113,8 +113,8 @@ module Errors = struct
     let title () = name in
     let message () = "" in
     let data = [
-      ("a" , fun () -> Format.asprintf "(%a)" PP.value a) ;
-      ("b" , fun () -> Format.asprintf "(%a)" PP.value b )
+      ("a" , fun () -> Format.asprintf "%a" PP.value a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.value b )
     ] in
     error ~data title message ()
 
diff --git a/src/bin/cli.ml b/src/bin/cli.ml
index 13ca1f970..be7626c86 100644
--- a/src/bin/cli.ml
+++ b/src/bin/cli.ml
@@ -46,7 +46,7 @@ let compile_file =
   let f source entry_point syntax =
     toplevel @@
     let%bind contract =
-      trace (simple_error "compile michelson") @@
+      trace (simple_info "compiling contract to michelson") @@
       Ligo.Run.compile_contract_file source entry_point syntax in
     Format.printf "Contract:\n%s\n" contract ;
     ok ()
diff --git a/src/operators/helpers.ml b/src/operators/helpers.ml
index a04f566f5..7cdc617f4 100644
--- a/src/operators/helpers.ml
+++ b/src/operators/helpers.ml
@@ -9,8 +9,17 @@ module Typer = struct
       let full () = Format.asprintf "constant name: %s\nexpected: %d\ngot: %d\n"
           name expected (List.length got) in
       error title full
-  end
 
+    let error_uncomparable_types a b () =
+      let title () = "these types are not comparable" in
+      let message () = "" in
+      let data = [
+        ("a" , fun () -> Format.asprintf "%a" PP.type_value a) ;
+        ("b" , fun () -> Format.asprintf "%a" PP.type_value b )
+      ] in
+      error ~data title message ()
+  end
+  open Errors
 
   type type_result = string * type_value
   type typer' = type_value list -> type_value option -> type_result result
@@ -22,7 +31,7 @@ module Typer = struct
       let%bind tv' = f tv_opt in
       ok (s , tv')
     )
-    | _ -> fail @@ Errors.wrong_param_number s 0 lst
+    | _ -> fail @@ wrong_param_number s 0 lst
   let typer_0 name f : typer = (name , typer'_0 name f)
 
   let typer'_1 : name -> (type_value -> type_value result) -> typer' = fun s f lst _ ->
@@ -31,7 +40,7 @@ module Typer = struct
         let%bind tv' = f a in
         ok (s , tv')
       )
-    | _ -> fail @@ Errors.wrong_param_number s 1 lst
+    | _ -> fail @@ wrong_param_number s 1 lst
   let typer_1 name f : typer = (name , typer'_1 name f)
 
   let typer'_1_opt : name -> (type_value -> type_value option -> type_value result) -> typer' = fun s f lst tv_opt ->
@@ -40,7 +49,7 @@ module Typer = struct
         let%bind tv' = f a tv_opt in
         ok (s , tv')
       )
-    | _ -> fail @@ Errors.wrong_param_number s 1 lst
+    | _ -> fail @@ wrong_param_number s 1 lst
   let typer_1_opt name f : typer = (name , typer'_1_opt name f)
 
   let typer'_2 : name -> (type_value -> type_value -> type_value result) -> typer' = fun s f lst _ ->
@@ -49,7 +58,7 @@ module Typer = struct
         let%bind tv' = f a b in
         ok (s , tv')
       )
-    | _ -> fail @@ Errors.wrong_param_number s 2 lst
+    | _ -> fail @@ wrong_param_number s 2 lst
   let typer_2 name f : typer = (name , typer'_2 name f)
 
   let typer'_3 : name -> (type_value -> type_value -> type_value -> type_value result) -> typer' = fun s f lst _ ->
@@ -58,7 +67,7 @@ module Typer = struct
         let%bind tv' = f a b c in
         ok (s , tv')
       )
-    | _ -> fail @@ Errors.wrong_param_number s 3 lst
+    | _ -> fail @@ wrong_param_number s 3 lst
   let typer_3 name f : typer = (name , typer'_3 name f)
 
   let constant name cst = typer_0 name (fun _ -> ok cst)
@@ -70,7 +79,7 @@ module Typer = struct
 
   let comparator : string -> typer = fun s -> typer_2 s @@ fun a b ->
     let%bind () =
-      trace_strong (simple_error "Types a and b aren't comparable") @@
+      trace_strong (error_uncomparable_types a b) @@
       Assert.assert_true @@
       List.exists (eq_2 (a , b)) [
         t_int () ;

From da4e3e5b807bf31fb56b680285fbf325a8bc5d8a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 19:17:42 +0200
Subject: [PATCH 07/19] improved --help docs

---
 src/bin/cli.ml | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/src/bin/cli.ml b/src/bin/cli.ml
index be7626c86..a17822a8b 100644
--- a/src/bin/cli.ml
+++ b/src/bin/cli.ml
@@ -53,8 +53,9 @@ let compile_file =
   in
   let term =
     Term.(const f $ source $ entry_point $ syntax) in
-  let docs = "Compile contracts." in
-  (term , Term.info ~docs "compile-contract")
+  let cmdname = "compile-contract" in
+  let docs = "Subcommand: compile a contract. See `ligo " ^ cmdname ^ " --help' for a list of options specific to this subcommand." in
+  (term , Term.info ~docs cmdname)
 
 let compile_parameter =
   let f source entry_point expression syntax =
@@ -67,8 +68,9 @@ let compile_parameter =
   in
   let term =
     Term.(const f $ source $ entry_point $ expression $ syntax) in
-  let docs = "Compile contracts parameters." in
-  (term , Term.info ~docs "compile-parameter")
+  let cmdname = "compile-parameter" in
+  let docs = "Subcommand: compile parameters to a michelson expression. The resulting michelson expression can be passed as an argument in a transaction which calls a contract. See `ligo " ^ cmdname ^ " --help' for a list of options specific to this subcommand." in
+  (term , Term.info ~docs cmdname)
 
 let compile_storage =
   let f source entry_point expression syntax =
@@ -81,8 +83,9 @@ let compile_storage =
   in
   let term =
     Term.(const f $ source $ entry_point $ expression $ syntax) in
-  let docs = "Compile contracts storage." in
-  (term , Term.info ~docs "compile-storage")
+  let cmdname = "compile-storage" in
+  let docs = "Subcommand: compile an initial storage in ligo syntax to a michelson expression. The resulting michelson expression can be passed as an argument in a transaction which originates a contract. See `ligo " ^ cmdname ^ " --help' for a list of options specific to this subcommand." in
+  (term , Term.info ~docs cmdname)
 
 
 let () = Term.exit @@ Term.eval_choice main [compile_file ; compile_parameter ; compile_storage]

From 02785aa75467e3a80aed03407224acf9686de001 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 19:19:44 +0200
Subject: [PATCH 08/19] Added failwith to camligo

---
 src/operators/operators.ml    | 8 ++++++++
 src/test/integration_tests.ml | 7 +++++++
 2 files changed, 15 insertions(+)

diff --git a/src/operators/operators.ml b/src/operators/operators.ml
index 6bec03b63..48fcd9a57 100644
--- a/src/operators/operators.ml
+++ b/src/operators/operators.ml
@@ -62,6 +62,7 @@ module Simplify = struct
       ("amount" , "AMOUNT") ;
       ("unit" , "UNIT") ;
       ("source" , "SOURCE") ;
+      ("failwith" , "FAILWITH") ;
     ]
 
     let type_constants = type_constants
@@ -149,6 +150,12 @@ module Typer = struct
       (is_t_map t || is_t_list t) in
     ok @@ t_nat ()
 
+  let failwith_ = typer_1 "FAILWITH" @@ fun t ->
+    let%bind () =
+      Assert.assert_true @@
+      (is_t_string t) in
+    ok @@ t_unit ()
+
   let get_force = typer_2 "MAP_GET_FORCE" @@ fun i m ->
     let%bind (src, dst) = get_t_map m in
     let%bind _ = assert_type_value_eq (src, i) in
@@ -246,6 +253,7 @@ module Typer = struct
       map_update ;
       int ;
       size ;
+      failwith_ ;
       get_force ;
       bytes_pack ;
       bytes_unpack ;
diff --git a/src/test/integration_tests.ml b/src/test/integration_tests.ml
index e303ac29f..f3b8dfa58 100644
--- a/src/test/integration_tests.ml
+++ b/src/test/integration_tests.ml
@@ -450,6 +450,12 @@ let counter_mligo () : unit result =
   let make_expected = fun n -> e_pair (e_typed_list [] t_operation) (e_int (42 + n)) in
   expect_eq_n program "main" make_input make_expected
 
+let failwith_mligo () : unit result =
+  let%bind program = mtype_file "./contracts/failwith.mligo" in
+  let make_input = e_pair (e_unit ()) (e_unit ()) in
+  let make_expected = e_pair (e_typed_list [] t_operation) (e_unit ()) in
+  expect_eq program "main" make_input make_expected
+
 let guess_the_hash_mligo () : unit result =
   let%bind program = mtype_file "./contracts/new-syntax.mligo" in
   let make_input = fun n-> e_pair (e_int n) (e_int 42) in
@@ -493,4 +499,5 @@ let main = test_suite "Integration (End to End)" [
     test "basic mligo" basic_mligo ;
     test "counter contract mligo" counter_mligo ;
     (* test "guess the hash mligo" guess_the_hash_mligo ; *)
+    (* test "failwith mligo" failwith_mligo ; *)
   ]

From a0624614eec377a9c917724931a146b08dbb9122 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 19:20:32 +0200
Subject: [PATCH 09/19] expect_eq_n: also test 1 (to check the cases 0, 1,
 many)

---
 src/test/test_helpers.ml | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/src/test/test_helpers.ml b/src/test/test_helpers.ml
index 03ae9e73d..57b8246f8 100644
--- a/src/test/test_helpers.ml
+++ b/src/test/test_helpers.ml
@@ -80,12 +80,12 @@ let expect_eq_n_aux ?options lst program entry_point make_input make_expected =
   let%bind _ = bind_map_list aux lst in
   ok ()
 
-let expect_eq_n ?options = expect_eq_n_aux ?options [0 ; 2 ; 42 ; 163 ; -1]
-let expect_eq_n_pos ?options = expect_eq_n_aux ?options [0 ; 2 ; 42 ; 163]
+let expect_eq_n ?options = expect_eq_n_aux ?options [0 ; 1 ; 2 ; 42 ; 163 ; -1]
+let expect_eq_n_pos ?options = expect_eq_n_aux ?options [0 ; 1 ; 2 ; 42 ; 163]
 let expect_eq_n_strict_pos ?options = expect_eq_n_aux ?options [2 ; 42 ; 163]
-let expect_eq_n_pos_small ?options = expect_eq_n_aux ?options [0 ; 2 ; 10]
-let expect_eq_n_strict_pos_small ?options = expect_eq_n_aux ?options [2 ; 10]
-let expect_eq_n_pos_mid = expect_eq_n_aux [0 ; 2 ; 10 ; 33]
+let expect_eq_n_pos_small ?options = expect_eq_n_aux ?options [0 ; 1 ; 2 ; 10]
+let expect_eq_n_strict_pos_small ?options = expect_eq_n_aux ?options [1 ; 2 ; 10]
+let expect_eq_n_pos_mid = expect_eq_n_aux [0 ; 1 ; 2 ; 10 ; 33]
 
 let expect_n_pos_small ?options = expect_n_aux ?options [0 ; 2 ; 10]
 let expect_n_strict_pos_small ?options = expect_n_aux ?options [2 ; 10]

From 08626f749ce4380807c0c10e3dc71bcf6f80479a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 19:18:16 +0200
Subject: [PATCH 10/19] "Guess the string" contract

---
 src/ast_typed/combinators.ml  | 5 +++++
 src/test/integration_tests.ml | 7 +++++++
 2 files changed, 12 insertions(+)

diff --git a/src/ast_typed/combinators.ml b/src/ast_typed/combinators.ml
index f5859806e..350836fc0 100644
--- a/src/ast_typed/combinators.ml
+++ b/src/ast_typed/combinators.ml
@@ -76,6 +76,10 @@ let get_t_bytes (t:type_value) : unit result = match t.type_value' with
   | T_constant ("bytes", []) -> ok ()
   | _ -> simple_fail "not a bytes"
 
+let get_t_string (t:type_value) : unit result = match t.type_value' with
+  | T_constant ("string", []) -> ok ()
+  | _ -> simple_fail "not a string"
+
 let get_t_contract (t:type_value) : type_value result = match t.type_value' with
   | T_constant ("contract", [x]) -> ok x
   | _ -> simple_fail "not a contract"
@@ -139,6 +143,7 @@ let assert_t_list t =
 
 let is_t_list = Function.compose to_bool get_t_list
 let is_t_nat = Function.compose to_bool get_t_nat
+let is_t_string = Function.compose to_bool get_t_string
 let is_t_int = Function.compose to_bool get_t_int
 
 let assert_t_bytes = fun t ->
diff --git a/src/test/integration_tests.ml b/src/test/integration_tests.ml
index f3b8dfa58..e11a88a82 100644
--- a/src/test/integration_tests.ml
+++ b/src/test/integration_tests.ml
@@ -462,6 +462,12 @@ let guess_the_hash_mligo () : unit result =
   let make_expected = fun n -> e_pair (e_typed_list [] t_operation) (e_int (42 + n)) in
   expect_eq_n program "main" make_input make_expected
 
+let guess_string_mligo () : unit result =
+  let%bind program = mtype_file "./contracts/guess_string.mligo" in
+  let make_input = fun n-> e_pair (e_int n) (e_int 42) in
+  let make_expected = fun n -> e_pair (e_typed_list [] t_operation) (e_int (42 + n)) in
+  expect_eq_n program "main" make_input make_expected
+
 let main = test_suite "Integration (End to End)" [
     test "type alias" type_alias ;
     test "function" function_ ;
@@ -500,4 +506,5 @@ let main = test_suite "Integration (End to End)" [
     test "counter contract mligo" counter_mligo ;
     (* test "guess the hash mligo" guess_the_hash_mligo ; *)
     (* test "failwith mligo" failwith_mligo ; *)
+    (* test "guess string mligo" guess_string_mligo ; *)
   ]

From dbe428265908e5749696c227875508a55c302eb7 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Wed, 5 Jun 2019 20:06:20 +0200
Subject: [PATCH 11/19] missing files in failwith and guess_string tests, oops.

---
 src/contracts/failwith.mligo     |  8 ++++++++
 src/contracts/guess_string.mligo | 24 ++++++++++++++++++++++++
 src/test/.gitignore              |  1 +
 3 files changed, 33 insertions(+)
 create mode 100644 src/contracts/failwith.mligo
 create mode 100644 src/contracts/guess_string.mligo
 create mode 100644 src/test/.gitignore

diff --git a/src/contracts/failwith.mligo b/src/contracts/failwith.mligo
new file mode 100644
index 000000000..91d7c42d6
--- /dev/null
+++ b/src/contracts/failwith.mligo
@@ -0,0 +1,8 @@
+type storage = unit
+
+(* let%entry main (p:unit) storage = *)
+(*   (failwith "This contract always fails" : unit) *)
+
+let%entry main (p:unit) storage =
+  if true then failwith "This contract always fails" else ()
+
diff --git a/src/contracts/guess_string.mligo b/src/contracts/guess_string.mligo
new file mode 100644
index 000000000..ae5bfd5bc
--- /dev/null
+++ b/src/contracts/guess_string.mligo
@@ -0,0 +1,24 @@
+(** Type of storage for this contract *)
+type storage = {
+  challenge : string ;
+}
+
+(** Initial storage *)
+let%init storage = {
+  challenge = "" ;
+}
+
+type param = {
+  new_challenge : string ;
+  attempt : string ;
+}
+
+let%entry attempt (p:param) storage =
+  (* if p.attempt <> storage.challenge then failwith "Failed challenge" else *)
+  let contract : unit contract = Operation.get_contract sender in
+  let transfer : operation = Operation.transaction (unit , contract , 10.00tz) in
+  (* TODO: no syntax for functional updates yet *)
+  (* let storage : storage = { storage with challenge = p.new_challenge } in *)
+  (* for now, rebuild the record by hand. *)
+  let storage : storage = { challenge = p.new_challenge } in
+  ((list [] : operation list), storage)
diff --git a/src/test/.gitignore b/src/test/.gitignore
new file mode 100644
index 000000000..ddabb4d33
--- /dev/null
+++ b/src/test/.gitignore
@@ -0,0 +1 @@
+/dune-project

From bff14309e4aff9ecaea94086f844c2686b624867 Mon Sep 17 00:00:00 2001
From: Christian Rinderknecht <Christian.Rinderknecht@tezcore.com>
Date: Thu, 6 Jun 2019 18:40:05 +0200
Subject: [PATCH 12/19] Predefined values for Ligodity. Added a few more tests
 for Ligodity.

---
 src/contracts/letin.mligo           |  7 ++++
 src/contracts/list.mligo            | 10 +++++
 src/contracts/match.mligo           | 13 +++++++
 src/contracts/new-syntax.mligo      | 14 ++++---
 src/contracts/record.mligo          | 47 +++++++++++++++++++++++
 src/operators/operators.ml          | 49 +++++++++++++++++++++++-
 src/parser/ligodity/Parser.mly      |  5 ++-
 src/parser/ligodity/Tests/match.mml | 13 +++++++
 src/test/integration_tests.ml       | 59 +++++++++++++++++++++--------
 9 files changed, 195 insertions(+), 22 deletions(-)
 create mode 100644 src/contracts/letin.mligo
 create mode 100644 src/contracts/list.mligo
 create mode 100644 src/contracts/match.mligo
 create mode 100644 src/contracts/record.mligo
 create mode 100644 src/parser/ligodity/Tests/match.mml

diff --git a/src/contracts/letin.mligo b/src/contracts/letin.mligo
new file mode 100644
index 000000000..fbdf8447c
--- /dev/null
+++ b/src/contracts/letin.mligo
@@ -0,0 +1,7 @@
+type storage = int * int
+
+let%entry main (n: int) storage =
+  let x : int * int =
+    let x : int = 7
+    in x + n, storage.(0) + storage.(1)
+  in (([] : operation list), x)
diff --git a/src/contracts/list.mligo b/src/contracts/list.mligo
new file mode 100644
index 000000000..31e2f7d50
--- /dev/null
+++ b/src/contracts/list.mligo
@@ -0,0 +1,10 @@
+type storage = int * int list
+
+type param = int list
+
+let%entry main (p : param) storage =
+  let storage =
+    match p with
+      [] -> storage
+    | hd::tl -> storage.(0) + hd, tl
+  in (([] : operation list), storage)
diff --git a/src/contracts/match.mligo b/src/contracts/match.mligo
new file mode 100644
index 000000000..1665e9f27
--- /dev/null
+++ b/src/contracts/match.mligo
@@ -0,0 +1,13 @@
+type storage = int
+
+type param =
+  Add of int
+| Sub of int
+
+let%entry main (p : param) storage =
+  let storage =
+    storage +
+      (match p with
+         Add n -> n
+       | Sub n -> 0-n)
+  in (([] : operation list), storage)
diff --git a/src/contracts/new-syntax.mligo b/src/contracts/new-syntax.mligo
index f2fed5396..e29aa6444 100644
--- a/src/contracts/new-syntax.mligo
+++ b/src/contracts/new-syntax.mligo
@@ -14,8 +14,12 @@ type param = {
 }
 
 let%entry attempt (p:param) storage =
-  if Crypto.hash (Bytes.pack p.attempt) <> Bytes.pack storage.challenge then failwith "Failed challenge" ;
-  let contract : unit contract = Operation.get_contract sender in
-  let transfer : operation = Operation.transaction (unit , contract , 10.00tz) in
-  let storage : storage = storage.challenge <- p.new_challenge in
-  ((list [] : operation list), storage)
+  if Crypto.hash (Bytes.pack p.attempt) <> Bytes.pack storage.challenge
+  then failwith "Failed challenge"
+  else
+    let contract : unit contract =
+      Operation.get_contract sender in
+    let transfer : operation =
+      Operation.transaction (unit , contract , 10tz) in
+    let storage : storage = {challenge = p.new_challenge}
+    in (([] : operation list), storage)
diff --git a/src/contracts/record.mligo b/src/contracts/record.mligo
new file mode 100644
index 000000000..943ccf91d
--- /dev/null
+++ b/src/contracts/record.mligo
@@ -0,0 +1,47 @@
+type foobar = {
+ foo : int ;
+ bar : int ;
+}
+
+let fb : foobar = {
+  foo = 0 ;
+  bar = 0 ;
+}
+
+type abc = {
+  a : int ;
+  b : int ;
+  c : int
+}
+
+let abc : abc = {
+  a = 42 ;
+  b = 142 ;
+  c = 242
+}
+
+let a : int = abc.a
+let b : int = abc.b
+let c : int = abc.c
+
+let projection (r : foobar) : int = r.foo + r.bar
+
+let modify (r : foobar) : foobar = {foo = 256; bar = r.bar}
+
+let modify_abc (r : abc) : abc = {a = r.a; b = 2048; c = r.c}
+
+type big_record = {
+     a : int ;
+     b : int ;
+     c : int ;
+     d : int ;
+     e : int ;
+}
+
+let br : big_record = {
+  a = 23 ;
+  b = 23 ;
+  c = 23 ;
+  d = 23 ;
+  e = 23 ;
+}
diff --git a/src/operators/operators.ml b/src/operators/operators.ml
index 48fcd9a57..c7665ea9d 100644
--- a/src/operators/operators.ml
+++ b/src/operators/operators.ml
@@ -83,7 +83,54 @@ module Simplify = struct
   end
 
   module Ligodity = struct
-    include Pascaligo
+    let constants = [
+      ("Current.balance", "BALANCE") ;
+      ("balance", "BALANCE") ;
+      ("Current.time", "NOW") ;
+      ("time", "NOW") ;
+      ("Current.amount" , "AMOUNT") ;
+      ("amount", "AMOUNT") ;
+      ("Current.gas", "STEPS_TO_QUOTA") ;
+      ("gas", "STEPS_TO_QUOTA") ;
+      ("Current.sender" , "SENDER") ;
+      ("sender", "SENDER") ;
+      ("Current.failwith", "FAILWITH") ;
+      ("failwith" , "FAILWITH") ;
+
+      ("Crypto.hash" , "HASH") ;
+      ("Crypto.black2b", "BLAKE2B") ;
+      ("Crypto.sha256", "SHA256") ;
+      ("Crypto.sha512", "SHA512") ;
+      ("Crypto.hash_key", "HASH_KEY") ;
+      ("Crypto.check", "CHECK_SIGNATURE") ;
+
+      ("Bytes.pack" , "PACK") ;
+      ("Bytes.unpack", "UNPACK") ;
+      ("Bytes.length", "SIZE") ;
+      ("Bytes.size" , "SIZE") ;
+      ("Bytes.concat", "CONCAT") ;
+      ("Bytes.slice", "SLICE") ;
+      ("Bytes.sub", "SLICE") ;
+
+      ("String.length", "SIZE") ;
+      ("String.size", "SIZE") ;
+      ("String.slice", "SLICE") ;
+      ("String.sub", "SLICE") ;
+      ("String.concat", "CONCAT") ;
+
+      ("List.length", "SIZE") ;
+      ("List.size", "SIZE") ;
+      ("List.iter", "ITER") ;
+
+      ("Operation.transaction" , "CALL") ;
+      ("Operation.get_contract" , "GET_CONTRACT") ;
+      ("int" , "INT") ;
+      ("abs" , "ABS") ;
+      ("unit" , "UNIT") ;
+      ("source" , "SOURCE") ;
+    ]
+
+    let type_constants = type_constants
   end
 
 end
diff --git a/src/parser/ligodity/Parser.mly b/src/parser/ligodity/Parser.mly
index cc76a8867..76267b6d3 100644
--- a/src/parser/ligodity/Parser.mly
+++ b/src/parser/ligodity/Parser.mly
@@ -5,9 +5,12 @@ open AST
 
 (* Rewrite "let pattern = e" as "let x = e;; let x1 = ...;; let x2 = ...;;" *)
 
+(*
 module VMap = Utils.String.Map
 
-(*let ghost_of value = Region.{region=ghost; value}*)
+let ghost_of value = Region.{region=ghost; value}
+*)
+
 let ghost = Region.ghost
 
 (* let fail_syn_unif type1 type2 : 'a =
diff --git a/src/parser/ligodity/Tests/match.mml b/src/parser/ligodity/Tests/match.mml
new file mode 100644
index 000000000..1665e9f27
--- /dev/null
+++ b/src/parser/ligodity/Tests/match.mml
@@ -0,0 +1,13 @@
+type storage = int
+
+type param =
+  Add of int
+| Sub of int
+
+let%entry main (p : param) storage =
+  let storage =
+    storage +
+      (match p with
+         Add n -> n
+       | Sub n -> 0-n)
+  in (([] : operation list), storage)
diff --git a/src/test/integration_tests.ml b/src/test/integration_tests.ml
index e11a88a82..cf93cc68d 100644
--- a/src/test/integration_tests.ml
+++ b/src/test/integration_tests.ml
@@ -439,17 +439,6 @@ let dispatch_counter_contract () : unit result =
     e_pair (e_typed_list [] t_operation) (e_int (op 42 n)) in
   expect_eq_n program "main" make_input make_expected
 
-let basic_mligo () : unit result =
-  let%bind typed = mtype_file ~debug_simplify:true "./contracts/basic.mligo" in
-  let%bind result = evaluate_typed "foo" typed in
-  Ligo.AST_Typed.assert_value_eq (Ligo.AST_Typed.Combinators.e_a_empty_int (42 + 127), result)
-
-let counter_mligo () : unit result =
-  let%bind program = mtype_file "./contracts/counter.mligo" in
-  let make_input = fun n-> e_pair (e_int n) (e_int 42) in
-  let make_expected = fun n -> e_pair (e_typed_list [] t_operation) (e_int (42 + n)) in
-  expect_eq_n program "main" make_input make_expected
-
 let failwith_mligo () : unit result =
   let%bind program = mtype_file "./contracts/failwith.mligo" in
   let make_input = e_pair (e_unit ()) (e_unit ()) in
@@ -464,10 +453,47 @@ let guess_the_hash_mligo () : unit result =
 
 let guess_string_mligo () : unit result =
   let%bind program = mtype_file "./contracts/guess_string.mligo" in
-  let make_input = fun n-> e_pair (e_int n) (e_int 42) in
-  let make_expected = fun n -> e_pair (e_typed_list [] t_operation) (e_int (42 + n)) in
+  let make_input = fun n -> e_pair (e_int n) (e_int 42) in
+  let make_expected = fun n -> e_pair (e_typed_list [] t_operation) (e_int (42 + n))
+  in expect_eq_n program "main" make_input make_expected
+
+let basic_mligo () : unit result =
+  let%bind typed = mtype_file ~debug_simplify:true "./contracts/basic.mligo" in
+  let%bind result = evaluate_typed "foo" typed in
+  Ligo.AST_Typed.assert_value_eq
+    (Ligo.AST_Typed.Combinators.e_a_empty_int (42 + 127), result)
+
+let counter_mligo () : unit result =
+  let%bind program = mtype_file "./contracts/counter.mligo" in
+  let make_input n = e_pair (e_int n) (e_int 42) in
+  let make_expected n = e_pair (e_typed_list [] t_operation) (e_int (42 + n)) in
   expect_eq_n program "main" make_input make_expected
 
+let let_in_mligo () : unit result =
+  let%bind program = mtype_file "./contracts/letin.mligo" in
+  let make_input n = e_pair (e_int n) (e_pair (e_int 3) (e_int 5)) in
+  let make_expected n =
+    e_pair (e_typed_list [] t_operation) (e_pair (e_int (7+n)) (e_int (3+5)))
+  in expect_eq_n program "main" make_input make_expected
+
+let match_variant () : unit result =
+  let%bind program = mtype_file "./contracts/match.mligo" in
+  let make_input n =
+    e_pair (e_constructor "Sub" (e_int n)) (e_int 3) in
+  let make_expected n =
+    e_pair (e_typed_list [] t_operation) (e_int (3-n))
+  in expect_eq_n program "main" make_input make_expected
+
+let mligo_list () : unit result =
+  let%bind program = mtype_file "./contracts/list.mligo" in
+  let make_input n =
+    e_pair (e_list [e_int n; e_int (2*n)])
+           (e_pair (e_int 3) (e_list [e_int 8])) in
+  let make_expected n =
+    e_pair (e_typed_list [] t_operation)
+      (e_pair (e_int (n+3)) (e_list [e_int (2*n)]))
+  in expect_eq_n program "main" make_input make_expected
+
 let main = test_suite "Integration (End to End)" [
     test "type alias" type_alias ;
     test "function" function_ ;
@@ -502,8 +528,11 @@ let main = test_suite "Integration (End to End)" [
     test "closure" closure ;
     test "shared function" shared_function ;
     test "higher order" higher_order ;
-    test "basic mligo" basic_mligo ;
-    test "counter contract mligo" counter_mligo ;
+    test "basic (mligo)" basic_mligo ;
+    test "counter contract (mligo)" counter_mligo ;
+    test "let-in (mligo)" let_in_mligo ;
+    test "match variant (mligo)" match_variant ;
+    (* test "list matching (mligo)" mligo_list ; *)
     (* test "guess the hash mligo" guess_the_hash_mligo ; *)
     (* test "failwith mligo" failwith_mligo ; *)
     (* test "guess string mligo" guess_string_mligo ; *)

From 0fea1c6d784473d0cbd1adfba79a288b67697626 Mon Sep 17 00:00:00 2001
From: Galfour <gabriel.alfour@gmail.com>
Date: Thu, 6 Jun 2019 17:37:46 +0000
Subject: [PATCH 13/19] improve bin pretty printing of errors

---
 src/bin/cli.ml | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/src/bin/cli.ml b/src/bin/cli.ml
index a17822a8b..b8423fc89 100644
--- a/src/bin/cli.ml
+++ b/src/bin/cli.ml
@@ -1,11 +1,34 @@
 open Cmdliner
 open Trace
 
+let error_pp out (e : error) =
+    let open JSON_string_utils in
+  let message =
+    let opt = e |> member "message" |> string in
+    let msg = Option.unopt ~default:"" opt in
+    ": " ^ msg in
+  let error_code =
+    let error_code = e |> member "error_code" in
+    match error_code with
+    | `Null -> ""
+    | _ -> " (" ^ (J.to_string error_code) ^ ")" in
+  let title =
+    let opt = e |> member "title" |> string in
+    Option.unopt ~default:"" opt in
+  let data =
+    let data = e |> member "data" in
+    match data with
+    | `Null -> ""
+    | _ -> " " ^ (J.to_string data) ^ "\n" in
+  Format.fprintf out "%s%s%s.\n%s" title error_code message data
+
+
 let toplevel x =
   match x with
   | Trace.Ok ((), annotations) -> ignore annotations; ()
-  | Error ss ->
+  | Error ss -> (
       Format.printf "%a%!" error_pp (ss ())
+    )
 
 let main =
   let term = Term.(const print_endline $ const "Ligo needs a command. Do ligo --help") in

From 0e36d63ec453cc7da607131867c7448612c78519 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Thu, 6 Jun 2019 20:48:36 +0200
Subject: [PATCH 14/19] more tests, improved error messages

---
 .../docs/language-basics-entrypoints.md       |  4 +-
 src/ast_simplified/misc.ml                    | 64 ++++++++++++++-----
 src/contracts/lambda.mligo                    |  9 +++
 src/contracts/lambda2.mligo                   | 10 +++
 src/contracts/website1.ligo                   |  2 +
 src/contracts/website2.ligo                   | 18 ++++++
 src/test/integration_tests.ml                 | 36 ++++++++++-
 src/typer/typer.ml                            | 39 ++++++-----
 8 files changed, 145 insertions(+), 37 deletions(-)
 create mode 100644 src/contracts/lambda.mligo
 create mode 100644 src/contracts/lambda2.mligo
 create mode 100644 src/contracts/website1.ligo
 create mode 100644 src/contracts/website2.ligo

diff --git a/gitlab-pages/docs/language-basics-entrypoints.md b/gitlab-pages/docs/language-basics-entrypoints.md
index ecb6ae65e..303cc88e7 100644
--- a/gitlab-pages/docs/language-basics-entrypoints.md
+++ b/gitlab-pages/docs/language-basics-entrypoints.md
@@ -8,7 +8,7 @@ title: Entrypoints
 <!--DOCUSAURUS_CODE_TABS-->
 <!--Pascaligo-->
 ```Pascal
-function main (const p : int ; const s : int) : (list(operation) * unit) is
+function main (const p : int ; const s : int) : (list(operation) * int) is
   block {skip} with ((nil : list(operation)), s + 1)
 ```
 <!--END_DOCUSAURUS_CODE_TABS-->
@@ -41,4 +41,4 @@ function main (const p : action ; const s : int) : (list(operation) * int) is
 ```
 
 
-<!--END_DOCUSAURUS_CODE_TABS-->
\ No newline at end of file
+<!--END_DOCUSAURUS_CODE_TABS-->
diff --git a/src/ast_simplified/misc.ml b/src/ast_simplified/misc.ml
index 05b8e2601..c857b8072 100644
--- a/src/ast_simplified/misc.ml
+++ b/src/ast_simplified/misc.ml
@@ -1,33 +1,63 @@
 open Trace
 open Types
 
+module Errors = struct
+  let different_literals_because_different_types name a b () =
+    let title () = "literals have different types: " ^ name in
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "%a" PP.literal a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.literal b )
+    ] in
+    error ~data title message ()
+
+  let different_literals name a b () =
+    let title () = name ^ " are different" in
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "%a" PP.literal a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.literal b )
+    ] in
+    error ~data title message ()
+
+  let error_uncomparable_literals name a b () =
+    let title () = name ^ " are not comparable" in
+    let message () = "" in
+    let data = [
+      ("a" , fun () -> Format.asprintf "%a" PP.literal a) ;
+      ("b" , fun () -> Format.asprintf "%a" PP.literal b )
+    ] in
+    error ~data title message ()
+end
+open Errors
+
 let assert_literal_eq (a, b : literal * literal) : unit result =
   match (a, b) with
   | Literal_bool a, Literal_bool b when a = b -> ok ()
-  | Literal_bool _, Literal_bool _ -> simple_fail "different bools"
-  | Literal_bool _, _ -> simple_fail "bool vs non-bool"
+  | Literal_bool _, Literal_bool _ -> fail @@ different_literals "different bools" a b
+  | Literal_bool _, _ -> fail @@ different_literals_because_different_types "bool vs non-bool" a b
   | Literal_int a, Literal_int b when a = b -> ok ()
-  | Literal_int _, Literal_int _ -> simple_fail "different ints"
-  | Literal_int _, _ -> simple_fail "int vs non-int"
+  | Literal_int _, Literal_int _ -> fail @@ different_literals "different ints" a b
+  | Literal_int _, _ -> fail @@ different_literals_because_different_types "int vs non-int" a b
   | Literal_nat a, Literal_nat b when a = b -> ok ()
-  | Literal_nat _, Literal_nat _ -> simple_fail "different nats"
-  | Literal_nat _, _ -> simple_fail "nat vs non-nat"
+  | Literal_nat _, Literal_nat _ -> fail @@ different_literals "different nats" a b
+  | Literal_nat _, _ -> fail @@ different_literals_because_different_types "nat vs non-nat" a b
   | Literal_tez a, Literal_tez b when a = b -> ok ()
-  | Literal_tez _, Literal_tez _ -> simple_fail "different tezs"
-  | Literal_tez _, _ -> simple_fail "tez vs non-tez"
+  | Literal_tez _, Literal_tez _ -> fail @@ different_literals "different tezs" a b
+  | Literal_tez _, _ -> fail @@ different_literals_because_different_types "tez vs non-tez" a b
   | Literal_string a, Literal_string b when a = b -> ok ()
-  | Literal_string _, Literal_string _ -> simple_fail "different strings"
-  | Literal_string _, _ -> simple_fail "string vs non-string"
+  | Literal_string _, Literal_string _ -> fail @@ different_literals "different strings" a b
+  | Literal_string _, _ -> fail @@ different_literals_because_different_types "string vs non-string" a b
   | Literal_bytes a, Literal_bytes b when a = b -> ok ()
-  | Literal_bytes _, Literal_bytes _ -> simple_fail "different bytess"
-  | Literal_bytes _, _ -> simple_fail "bytes vs non-bytes"
+  | Literal_bytes _, Literal_bytes _ -> fail @@ different_literals "different bytess" a b
+  | Literal_bytes _, _ -> fail @@ different_literals_because_different_types "bytes vs non-bytes" a b
   | Literal_unit, Literal_unit -> ok ()
-  | Literal_unit, _ -> simple_fail "unit vs non-unit"
+  | Literal_unit, _ -> fail @@ different_literals_because_different_types "unit vs non-unit" a b
   | Literal_address a, Literal_address b when a = b -> ok ()
-  | Literal_address _, Literal_address _ -> simple_fail "different addresss"
-  | Literal_address _, _ -> simple_fail "address vs non-address"
-  | Literal_operation _, Literal_operation _ -> simple_fail "can't compare operations"
-  | Literal_operation _, _ -> simple_fail "operation vs non-operation"
+  | Literal_address _, Literal_address _ -> fail @@ different_literals "different addresss" a b
+  | Literal_address _, _ -> fail @@ different_literals_because_different_types "address vs non-address" a b
+  | Literal_operation _, Literal_operation _ -> fail @@ error_uncomparable_literals "can't compare operations" a b
+  | Literal_operation _, _ -> fail @@ different_literals_because_different_types "operation vs non-operation" a b
 
 
 let rec assert_value_eq (a, b: (expression * expression )) : unit result =
diff --git a/src/contracts/lambda.mligo b/src/contracts/lambda.mligo
new file mode 100644
index 000000000..1f9ada31a
--- /dev/null
+++ b/src/contracts/lambda.mligo
@@ -0,0 +1,9 @@
+type storage = unit
+
+(* not supported yet
+let%entry main (p:unit) storage =
+  (fun x -> ()) ()
+*)
+
+let%entry main (p:unit) storage =
+  (fun (x : unit) -> ()) ()
diff --git a/src/contracts/lambda2.mligo b/src/contracts/lambda2.mligo
new file mode 100644
index 000000000..290ddef27
--- /dev/null
+++ b/src/contracts/lambda2.mligo
@@ -0,0 +1,10 @@
+type storage = unit
+
+(* not supported yet
+let%entry main (p:unit) storage =
+  (fun x -> ()) ()
+*)
+
+let%entry main (p:unit) storage =
+  (fun (f : unit -> unit) -> f ())
+    (fun (x : unit) -> unit)
diff --git a/src/contracts/website1.ligo b/src/contracts/website1.ligo
new file mode 100644
index 000000000..4c8272d64
--- /dev/null
+++ b/src/contracts/website1.ligo
@@ -0,0 +1,2 @@
+function main (const p : int ; const s : int) : (list(operation) * int) is
+  block {skip} with ((nil : list(operation)), s + 1)
diff --git a/src/contracts/website2.ligo b/src/contracts/website2.ligo
new file mode 100644
index 000000000..25b36a880
--- /dev/null
+++ b/src/contracts/website2.ligo
@@ -0,0 +1,18 @@
+// variant defining pseudo multi-entrypoint actions
+type action is
+| Increment of int
+| Decrement of int
+
+function add (const a : int ; const b : int) : int is
+    block { skip } with a + b
+
+function subtract (const a : int ; const b : int) : int is
+    block { skip } with a - b
+
+// real entrypoint that re-routes the flow based on the action provided
+function main (const p : action ; const s : int) : (list(operation) * int) is
+  block {skip} with ((nil : list(operation)),
+    case p of
+    | Increment n -> add(s, n)
+    | Decrement n -> subtract(s, n)
+    end)
diff --git a/src/test/integration_tests.ml b/src/test/integration_tests.ml
index cf93cc68d..ad7066bb7 100644
--- a/src/test/integration_tests.ml
+++ b/src/test/integration_tests.ml
@@ -494,6 +494,34 @@ let mligo_list () : unit result =
       (e_pair (e_int (n+3)) (e_list [e_int (2*n)]))
   in expect_eq_n program "main" make_input make_expected
 
+let lambda_mligo () : unit result =
+  let%bind program = mtype_file "./contracts/lambda.mligo" in
+  let make_input = e_pair (e_unit ()) (e_unit ()) in
+  let make_expected = (e_unit ()) in
+  expect_eq program "main" make_input make_expected
+
+let lambda2_mligo () : unit result =
+  let%bind program = mtype_file "./contracts/lambda2.mligo" in
+  let make_input = e_pair (e_unit ()) (e_unit ()) in
+  let make_expected = (e_unit ()) in
+  expect_eq program "main" make_input make_expected
+
+let website1_ligo () : unit result =
+  let%bind program = type_file "./contracts/website1.ligo" in
+  let make_input = fun n-> e_pair (e_int n) (e_int 42) in
+  let make_expected = fun _n -> e_pair (e_typed_list [] t_operation) (e_int (42 + 1)) in
+  expect_eq_n program "main" make_input make_expected
+
+let website2_ligo () : unit result =
+  let%bind program = type_file "./contracts/website2.ligo" in
+  let make_input = fun n ->
+    let action = if n mod 2 = 0 then "Increment" else "Decrement" in
+    e_pair (e_constructor action (e_int n)) (e_int 42) in
+  let make_expected = fun n ->
+    let op = if n mod 2 = 0 then (+) else (-) in
+    e_pair (e_typed_list [] t_operation) (e_int (op 42 n)) in
+  expect_eq_n program "main" make_input make_expected
+
 let main = test_suite "Integration (End to End)" [
     test "type alias" type_alias ;
     test "function" function_ ;
@@ -533,7 +561,11 @@ let main = test_suite "Integration (End to End)" [
     test "let-in (mligo)" let_in_mligo ;
     test "match variant (mligo)" match_variant ;
     (* test "list matching (mligo)" mligo_list ; *)
-    (* test "guess the hash mligo" guess_the_hash_mligo ; *)
+    (* test "guess the hash mligo" guess_the_hash_mligo ; WIP? *)
     (* test "failwith mligo" failwith_mligo ; *)
-    (* test "guess string mligo" guess_string_mligo ; *)
+    (* test "guess string mligo" guess_string_mligo ; WIP? *)
+    (* test "lambda mligo" lambda_mligo ; *)
+    (* test "lambda2 mligo" lambda2_mligo ; *)
+    test "website1 ligo" website1_ligo ;
+    test "website2 ligo" website2_ligo ;
   ]
diff --git a/src/typer/typer.ml b/src/typer/typer.ml
index 0f4c6d0a9..99d49144d 100644
--- a/src/typer/typer.ml
+++ b/src/typer/typer.ml
@@ -145,24 +145,24 @@ module Errors = struct
     ] in
     error ~data title message ()
 
-  let type_error_approximate ?(msg="") ~(expected: string) ~(actual: O.type_value) ~(expression : O.value) (loc:Location.t) () =
+  let type_error_approximate ?(msg="") ~(expected: string) ~(actual: O.type_value) ~(expression : I.expression) (loc:Location.t) () =
     let title = (thunk "type error") in
     let message () = msg in
     let data = [
       ("expected"   , fun () -> Format.asprintf "%s" expected);
       ("actual"     , fun () -> Format.asprintf "%a" O.PP.type_value actual);
-      ("expression" , fun () -> Format.asprintf "%a" O.PP.value expression) ;
+      ("expression" , fun () -> Format.asprintf "%a" I.PP.expression expression) ;
       ("location" , fun () -> Format.asprintf "%a" Location.pp loc)
     ] in
     error ~data title message ()
 
-  let type_error ?(msg="") ~(expected: O.type_value) ~(actual: O.type_value) ~(expression : O.value) (loc:Location.t) () =
+  let type_error ?(msg="") ~(expected: O.type_value) ~(actual: O.type_value) ~(expression : I.expression) (loc:Location.t) () =
     let title = (thunk "type error") in
     let message () = msg in
     let data = [
       ("expected"   , fun () -> Format.asprintf "%a" O.PP.type_value expected);
       ("actual"     , fun () -> Format.asprintf "%a" O.PP.type_value actual);
-      ("expression" , fun () -> Format.asprintf "%a" O.PP.value expression) ;
+      ("expression" , fun () -> Format.asprintf "%a" I.PP.expression expression) ;
       ("location" , fun () -> Format.asprintf "%a" Location.pp loc)
     ] in
     error ~data title message ()
@@ -237,8 +237,8 @@ and type_declaration env : I.declaration -> (environment * O.declaration option)
       ok (env', Some (O.Declaration_constant ((make_n_e name ae') , (env , env'))))
     )
 
-and type_match : type i o . (environment -> i -> o result) -> environment -> O.type_value -> i I.matching -> Location.t -> o O.matching result =
-  fun f e t i loc -> match i with
+and type_match : type i o . (environment -> i -> o result) -> environment -> O.type_value -> i I.matching -> I.expression -> Location.t -> o O.matching result =
+  fun f e t i ae loc -> match i with
     | Match_bool {match_true ; match_false} ->
       let%bind _ =
         trace_strong (match_error ~expected:i ~actual:t loc)
@@ -286,6 +286,13 @@ and type_match : type i o . (environment -> i -> o result) -> environment -> O.t
           let%bind acc = match acc with
             | None -> ok (Some variant)
             | Some variant' -> (
+                trace (type_error
+                         ~msg:"in match variant"
+                         ~expected:variant
+                         ~actual:variant'
+                         ~expression:ae
+                         loc
+                      ) @@
                 Ast_typed.assert_type_value_eq (variant , variant') >>? fun () ->
                 ok (Some variant)
               ) in
@@ -559,9 +566,9 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
       let%bind (name', tv) = type_constant name tv_lst tv_opt ae.location in
       return (E_constant (name' , lst')) tv
   | E_application (f, arg) ->
-      let%bind f = type_expression e f in
+      let%bind f' = type_expression e f in
       let%bind arg = type_expression e arg in
-      let%bind tv = match f.type_annotation.type_value' with
+      let%bind tv = match f'.type_annotation.type_value' with
         | T_function (param, result) ->
             let%bind _ = O.assert_type_value_eq (param, arg.type_annotation) in
             ok result
@@ -569,10 +576,10 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
           fail @@ type_error_approximate
             ~expected:"should be a function type"
             ~expression:f
-            ~actual:f.type_annotation
-            f.location
+            ~actual:f'.type_annotation
+            f'.location
       in
-      return (E_application (f , arg)) tv
+      return (E_application (f' , arg)) tv
   | E_look_up dsi ->
       let%bind (ds, ind) = bind_map_pair (type_expression e) dsi in
       let%bind (src, dst) = get_t_map ds.type_annotation in
@@ -607,7 +614,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
           return (O.E_matching (ex' , m')) (t_unit ())
         )
       | _ -> (
-          let%bind m' = type_match (type_expression ?tv_opt:None) e ex'.type_annotation m ae.location in
+          let%bind m' = type_match (type_expression ?tv_opt:None) e ex'.type_annotation m ae ae.location in
           let tvs =
             let aux (cur:O.value O.matching) =
               match cur with
@@ -639,7 +646,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
                       ~msg:"first part of the sequence should be of unit type"
                       ~expected:(O.t_unit ())
                       ~actual:a'_type_annot
-                      ~expression:a'
+                      ~expression:a
                       a'.location) @@
       Ast_typed.assert_type_value_eq (t_unit () , a'_type_annot) in
     return (O.E_sequence (a' , b')) (get_type_annotation b')
@@ -652,7 +659,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
                       ~msg:"while condition isn't of type bool"
                       ~expected:(O.t_bool ())
                       ~actual:t_expr'
-                      ~expression:expr'
+                      ~expression:expr
                       expr'.location) @@
       Ast_typed.assert_type_value_eq (t_bool () , t_expr') in
     let t_body' = get_type_annotation body' in
@@ -661,7 +668,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
                      ~msg:"while body isn't of unit type"
                      ~expected:(O.t_unit ())
                      ~actual:t_body'
-                     ~expression:body'
+                     ~expression:body
                      body'.location) @@
       Ast_typed.assert_type_value_eq (t_unit () , t_body') in
     return (O.E_loop (expr' , body')) (t_unit ())
@@ -697,7 +704,7 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
                      ~msg:"type of the expression to assign doesn't match left-hand-side"
                      ~expected:assign_tv
                      ~actual:t_expr'
-                     ~expression:expr'
+                     ~expression:expr
                      expr'.location) @@
       Ast_typed.assert_type_value_eq (assign_tv , t_expr') in
     return (O.E_assign (typed_name , path' , expr')) (t_unit ())

From a4f895882f8c93f1d25eb74132e75a705a9224ac Mon Sep 17 00:00:00 2001
From: Galfour <gabriel.alfour@gmail.com>
Date: Thu, 6 Jun 2019 20:49:36 +0000
Subject: [PATCH 15/19] more error messages; various fixes

---
 src/ast_typed/combinators.ml  |  1 +
 src/bin/cli.ml                | 17 ++++++++++++-----
 src/compiler/compiler_type.ml |  3 +++
 src/mini_c/PP.ml              |  1 +
 src/mini_c/types.ml           |  1 +
 src/operators/operators.ml    | 30 +++++++++++++++++++++---------
 src/simplify/pascaligo.ml     |  2 +-
 src/transpiler/transpiler.ml  |  1 +
 src/typer/typer.ml            | 26 +++++++++++++++++---------
 9 files changed, 58 insertions(+), 24 deletions(-)

diff --git a/src/ast_typed/combinators.ml b/src/ast_typed/combinators.ml
index 350836fc0..a6d34c72a 100644
--- a/src/ast_typed/combinators.ml
+++ b/src/ast_typed/combinators.ml
@@ -20,6 +20,7 @@ let t_address ?s () : type_value = make_t (T_constant ("address", [])) s
 let t_operation ?s () : type_value = make_t (T_constant ("operation", [])) s
 let t_nat ?s () : type_value = make_t (T_constant ("nat", [])) s
 let t_tez ?s () : type_value = make_t (T_constant ("tez", [])) s
+let t_timestamp ?s () : type_value = make_t (T_constant ("timestamp", [])) s
 let t_unit ?s () : type_value = make_t (T_constant ("unit", [])) s
 let t_option o ?s () : type_value = make_t (T_constant ("option", [o])) s
 let t_tuple lst ?s () : type_value = make_t (T_tuple lst) s
diff --git a/src/bin/cli.ml b/src/bin/cli.ml
index c65b45f3f..f7fb287f3 100644
--- a/src/bin/cli.ml
+++ b/src/bin/cli.ml
@@ -6,7 +6,9 @@ let error_pp out (e : error) =
   let message =
     let opt = e |> member "message" |> string in
     let msg = Option.unopt ~default:"" opt in
-    ": " ^ msg in
+    if msg = ""
+    then ""
+    else ": " ^ msg in
   let error_code =
     let error_code = e |> member "error_code" in
     match error_code with
@@ -20,7 +22,12 @@ let error_pp out (e : error) =
     match data with
     | `Null -> ""
     | _ -> " " ^ (J.to_string data) ^ "\n" in
-  Format.fprintf out "%s%s%s.\n%s" title error_code message data
+  let infos =
+    let infos = e |> member "infos" in
+    match infos with
+    | `Null -> ""
+    | _ -> " " ^ (J.to_string infos) ^ "\n" in
+  Format.fprintf out "%s%s%s.\n%s%s" title error_code message data infos
 
 
 let toplevel x =
@@ -71,7 +78,7 @@ let compile_file =
     let%bind contract =
       trace (simple_info "compiling contract to michelson") @@
       Ligo.Run.compile_contract_file source entry_point syntax in
-    Format.printf "Contract:\n%s\n" contract ;
+    Format.printf "%s\n" contract ;
     ok ()
   in
   let term =
@@ -86,7 +93,7 @@ let compile_parameter =
     let%bind value =
       trace (simple_error "compile-input") @@
       Ligo.Run.compile_contract_parameter source entry_point expression syntax in
-    Format.printf "Input:\n%s\n" value;
+    Format.printf "%s\n" value;
     ok ()
   in
   let term =
@@ -101,7 +108,7 @@ let compile_storage =
     let%bind value =
       trace (simple_error "compile-storage") @@
       Ligo.Run.compile_contract_storage source entry_point expression syntax in
-    Format.printf "Storage:\n%s\n" value;
+    Format.printf "%s\n" value;
     ok ()
   in
   let term =
diff --git a/src/compiler/compiler_type.ml b/src/compiler/compiler_type.ml
index 20daf075c..18ea463cf 100644
--- a/src/compiler/compiler_type.ml
+++ b/src/compiler/compiler_type.ml
@@ -22,6 +22,7 @@ module Ty = struct
     | Base_int -> return int_k
     | Base_string -> return string_k
     | Base_address -> return address_k
+    | Base_timestamp -> return timestamp_k
     | Base_bytes -> return bytes_k
     | Base_operation -> fail (not_comparable "operation")
 
@@ -48,6 +49,7 @@ module Ty = struct
     | Base_tez -> return tez
     | Base_string -> return string
     | Base_address -> return address
+    | Base_timestamp -> return timestamp
     | Base_bytes -> return bytes
     | Base_operation -> return operation
 
@@ -117,6 +119,7 @@ let base_type : type_base -> O.michelson result =
   | Base_tez -> ok @@ O.prim T_mutez
   | Base_string -> ok @@ O.prim T_string
   | Base_address -> ok @@ O.prim T_address
+  | Base_timestamp -> ok @@ O.prim T_timestamp
   | Base_bytes -> ok @@ O.prim T_bytes
   | Base_operation -> ok @@ O.prim T_operation
 
diff --git a/src/mini_c/PP.ml b/src/mini_c/PP.ml
index 895b0754a..51867e490 100644
--- a/src/mini_c/PP.ml
+++ b/src/mini_c/PP.ml
@@ -16,6 +16,7 @@ let type_base ppf : type_base -> _ = function
   | Base_tez -> fprintf ppf "tez"
   | Base_string -> fprintf ppf "string"
   | Base_address -> fprintf ppf "address"
+  | Base_timestamp -> fprintf ppf "timestamp"
   | Base_bytes -> fprintf ppf "bytes"
   | Base_operation -> fprintf ppf "operation"
 
diff --git a/src/mini_c/types.ml b/src/mini_c/types.ml
index ca445ee0e..6e5bb4906 100644
--- a/src/mini_c/types.ml
+++ b/src/mini_c/types.ml
@@ -4,6 +4,7 @@ type type_base =
   | Base_unit
   | Base_bool
   | Base_int | Base_nat | Base_tez
+  | Base_timestamp
   | Base_string | Base_bytes | Base_address
   | Base_operation
 
diff --git a/src/operators/operators.ml b/src/operators/operators.ml
index c7665ea9d..afb5d34af 100644
--- a/src/operators/operators.ml
+++ b/src/operators/operators.ml
@@ -42,6 +42,7 @@ module Simplify = struct
     ("bool" , "bool") ;
     ("operation" , "operation") ;
     ("address" , "address") ;
+    ("timestamp" , "timestamp") ;
     ("contract" , "contract") ;
     ("list" , "list") ;
     ("option" , "option") ;
@@ -60,8 +61,10 @@ module Simplify = struct
       ("int" , "INT") ;
       ("abs" , "ABS") ;
       ("amount" , "AMOUNT") ;
+      ("now" , "NOW") ;
       ("unit" , "UNIT") ;
       ("source" , "SOURCE") ;
+      ("sender" , "SENDER") ;
       ("failwith" , "FAILWITH") ;
     ]
 
@@ -169,14 +172,15 @@ module Typer = struct
     | Some t -> ok t
 
   let sub = typer_2 "SUB" @@ fun a b ->
-    let%bind () =
-      trace_strong (simple_error "Types a and b aren't numbers") @@
-      Assert.assert_true @@
-      List.exists (eq_2 (a , b)) [
-        t_int () ;
-        t_nat () ;
-      ] in
-    ok @@ t_int ()
+    if (eq_2 (a , b) (t_int ()))
+    then ok @@ t_int () else
+    if (eq_2 (a , b) (t_nat ()))
+    then ok @@ t_int () else
+    if (eq_2 (a , b) (t_timestamp ()))
+    then ok @@ t_int () else
+    if (eq_2 (a , b) (t_tez ()))
+    then ok @@ t_tez () else
+      fail (simple_error "Typing substraction, bad parameters.")
 
   let some = typer_1 "SOME" @@ fun a -> ok @@ t_option a ()
 
@@ -232,6 +236,8 @@ module Typer = struct
 
   let amount = constant "AMOUNT" @@ t_tez ()
 
+  let now = constant "NOW" @@ t_timestamp ()
+
   let transaction = typer_3 "CALL" @@ fun param amount contract ->
     let%bind () = assert_t_tez amount in
     let%bind contract_param = get_t_contract contract in
@@ -264,6 +270,8 @@ module Typer = struct
     then ok @@ t_nat () else
     if eq_2 (a , b) (t_int ())
     then ok @@ t_int () else
+    if eq_1 a (t_tez ()) && eq_1 b (t_nat ())
+    then ok @@ t_tez () else
       simple_fail "Dividing with wrong types"
 
   let mod_ = typer_2 "MOD" @@ fun a b ->
@@ -276,9 +284,11 @@ module Typer = struct
     then ok @@ t_nat () else
     if eq_2 (a , b) (t_int ())
     then ok @@ t_int () else
+    if eq_2 (a , b) (t_tez ())
+    then ok @@ t_tez () else
     if (eq_1 a (t_nat ()) && eq_1 b (t_int ())) || (eq_1 b (t_nat ()) && eq_1 a (t_int ()))
     then ok @@ t_int () else
-      simple_fail "Adding with wrong types"
+      simple_fail "Adding with wrong types. Expected nat, int or tez."
 
   let constant_typers = Map.String.of_list [
       add ;
@@ -312,6 +322,7 @@ module Typer = struct
       transaction ;
       get_contract ;
       abs ;
+      now ;
     ]
 
 end
@@ -364,6 +375,7 @@ module Compiler = struct
     ("CONS" , simple_binary @@ prim I_CONS) ;
     ("UNIT" , simple_constant @@ prim I_UNIT) ;
     ("AMOUNT" , simple_constant @@ prim I_AMOUNT) ;
+    ("NOW" , simple_constant @@ prim I_NOW) ;
     ("CALL" , simple_ternary @@ prim I_TRANSFER_TOKENS) ;
     ("SOURCE" , simple_constant @@ prim I_SOURCE) ;
     ("SENDER" , simple_constant @@ prim I_SENDER) ;
diff --git a/src/simplify/pascaligo.ml b/src/simplify/pascaligo.ml
index 6925d2ba5..58b5d6896 100644
--- a/src/simplify/pascaligo.ml
+++ b/src/simplify/pascaligo.ml
@@ -346,7 +346,7 @@ let rec simpl_type_expression (t:Raw.type_expr) : type_expression result =
 
 and simpl_list_type_expression (lst:Raw.type_expr list) : type_expression result =
   match lst with
-  | [] -> assert false
+  | [] -> ok @@ t_unit
   | [hd] -> simpl_type_expression hd
   | lst ->
       let%bind lst = bind_list @@ List.map simpl_type_expression lst in
diff --git a/src/transpiler/transpiler.ml b/src/transpiler/transpiler.ml
index 4b27b2dcc..724a32b32 100644
--- a/src/transpiler/transpiler.ml
+++ b/src/transpiler/transpiler.ml
@@ -93,6 +93,7 @@ let rec translate_type (t:AST.type_value) : type_value result =
   | T_constant ("tez", []) -> ok (T_base Base_tez)
   | T_constant ("string", []) -> ok (T_base Base_string)
   | T_constant ("address", []) -> ok (T_base Base_address)
+  | T_constant ("timestamp", []) -> ok (T_base Base_timestamp)
   | T_constant ("unit", []) -> ok (T_base Base_unit)
   | T_constant ("operation", []) -> ok (T_base Base_operation)
   | T_constant ("contract", [x]) ->
diff --git a/src/typer/typer.ml b/src/typer/typer.ml
index 99d49144d..a3f0f0140 100644
--- a/src/typer/typer.ml
+++ b/src/typer/typer.ml
@@ -206,6 +206,13 @@ module Errors = struct
     ] in
     error ~data title message ()
 
+  let constant_error loc =
+    let title () = "typing constant" in
+    let message () = "" in
+    let data = [
+      ("location" , fun () -> Format.asprintf "%a" Location.pp loc ) ;
+    ] in
+    error ~data title message
 end
 open Errors
 
@@ -377,14 +384,13 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
     ok @@ make_a_e ~location expr tv e in
   let main_error =
     let title () = "typing expression" in
-    let content () =
-      match L.get () with
-      | "" ->
-        Format.asprintf "Expression: %a\n" I.PP.expression ae
-      | l ->
-        Format.asprintf "Expression: %a\nLog: %s\n" I.PP.expression ae l
-    in
-    error title content in
+    let content () = "" in
+    let data = [
+      ("expression" , fun () -> Format.asprintf "%a" I.PP.expression ae) ;
+      ("location" , fun () -> Format.asprintf "%a" Location.pp @@ Location.get_location ae) ;
+      ("misc" , fun () -> L.get ()) ;
+    ] in
+    error ~data title content in
   trace main_error @@
   match Location.unwrap ae with
   (* Basic *)
@@ -563,7 +569,8 @@ and type_expression : environment -> ?tv_opt:O.type_value -> I.expression -> O.a
   | E_constant (name, lst) ->
       let%bind lst' = bind_list @@ List.map (type_expression e) lst in
       let tv_lst = List.map get_type_annotation lst' in
-      let%bind (name', tv) = type_constant name tv_lst tv_opt ae.location in
+      let%bind (name', tv) =
+        type_constant name tv_lst tv_opt ae.location in
       return (E_constant (name' , lst')) tv
   | E_application (f, arg) ->
       let%bind f' = type_expression e f in
@@ -731,6 +738,7 @@ and type_constant (name:string) (lst:O.type_value list) (tv_opt:O.type_value opt
   let%bind typer =
     trace_option (unrecognized_constant name loc) @@
     Map.String.find_opt name ct in
+  trace (constant_error loc) @@
   typer lst tv_opt
 
 let untype_type_value (t:O.type_value) : (I.type_expression) result =

From 346a6fdbc4d258ee7bf86e44f4c157444bf0201c Mon Sep 17 00:00:00 2001
From: Galfour <gabriel.alfour@gmail.com>
Date: Thu, 6 Jun 2019 21:06:33 +0000
Subject: [PATCH 16/19] hide compiler errors; fix ligodity's over-eager
 tuplification

---
 src/compiler/compiler_program.ml | 18 ++++++++++++-
 src/simplify/ligodity.ml         | 45 ++++++++++++++++++++------------
 src/test/integration_tests.ml    |  2 +-
 src/test/test_helpers.ml         | 29 ++++++++++++++++++++
 4 files changed, 76 insertions(+), 18 deletions(-)

diff --git a/src/compiler/compiler_program.ml b/src/compiler/compiler_program.ml
index e5b5b6632..db8e7936e 100644
--- a/src/compiler/compiler_program.ml
+++ b/src/compiler/compiler_program.ml
@@ -464,8 +464,24 @@ let translate_entry (p:anon_function) : compiled_program result =
   let%bind output = Compiler_type.Ty.type_ output in
   ok ({input;output;body}:compiled_program)
 
+module Errors = struct
+  let corner_case ~loc message =
+    let title () = "corner case" in
+    let content () = "we don't have a good error message for this case. we are
+striving find ways to better report them and find the use-cases that generate
+them. please report this to the developers." in
+    let data = [
+      ("location" , fun () -> loc) ;
+      ("message" , fun () -> message) ;
+    ] in
+    error ~data title content
+end
+open Errors
+
 let translate_contract : anon_function -> michelson result = fun f ->
-  let%bind compiled_program = translate_entry f in
+  let%bind compiled_program =
+    trace_strong (corner_case ~loc:__LOC__ "compiling") @@
+    translate_entry f in
   let%bind (param_ty , storage_ty) = Combinators.get_t_pair f.input in
   let%bind param_michelson = Compiler_type.type_ param_ty in
   let%bind storage_michelson = Compiler_type.type_ storage_ty in
diff --git a/src/simplify/ligodity.ml b/src/simplify/ligodity.ml
index e938ad285..cd3a4472d 100644
--- a/src/simplify/ligodity.ml
+++ b/src/simplify/ligodity.ml
@@ -479,22 +479,35 @@ and simpl_fun lamb' : expr result =
     in
     bind_map_list aux p_args
   in
-  let arguments_name = "arguments" in
-  let (binder , input_type) =
-    let type_expression = T_tuple (List.map snd args') in
-    (arguments_name , type_expression) in
-  let%bind (body , body_type) = expr_to_typed_expr lamb.body in
-  let%bind output_type =
-    bind_map_option simpl_type_expression body_type in
-  let%bind result = simpl_expression body in
-  let wrapped_result =
-    let aux = fun i ((name : Raw.variable) , ty) wrapped ->
-      let accessor = e_accessor (e_variable arguments_name) [ Access_tuple i ] in
-      e_let_in (name.value , Some ty) accessor wrapped
-    in
-    let wraps = List.mapi aux args' in
-    List.fold_right' (fun x f -> f x) result wraps in
-  return @@ e_lambda ~loc binder (Some input_type) output_type wrapped_result
+  match args' with
+  | [ single ] -> (
+      let (binder , input_type) =
+        ((fst single).value , snd single) in
+      let%bind (body , body_type) = expr_to_typed_expr lamb.body in
+      let%bind output_type =
+        bind_map_option simpl_type_expression body_type in
+      let%bind result = simpl_expression body in
+      return @@ e_lambda ~loc binder (Some input_type) output_type result
+
+    )
+  | _ -> (
+      let arguments_name = "arguments" in
+      let (binder , input_type) =
+        let type_expression = T_tuple (List.map snd args') in
+        (arguments_name , type_expression) in
+      let%bind (body , body_type) = expr_to_typed_expr lamb.body in
+      let%bind output_type =
+        bind_map_option simpl_type_expression body_type in
+      let%bind result = simpl_expression body in
+      let wrapped_result =
+        let aux = fun i ((name : Raw.variable) , ty) wrapped ->
+          let accessor = e_accessor (e_variable arguments_name) [ Access_tuple i ] in
+          e_let_in (name.value , Some ty) accessor wrapped
+        in
+        let wraps = List.mapi aux args' in
+        List.fold_right' (fun x f -> f x) result wraps in
+      return @@ e_lambda ~loc binder (Some input_type) output_type wrapped_result
+    )
 
 
 and simpl_logic_expression ?te_annot (t:Raw.logic_expr) : expr result =
diff --git a/src/test/integration_tests.ml b/src/test/integration_tests.ml
index ad7066bb7..ba9db500c 100644
--- a/src/test/integration_tests.ml
+++ b/src/test/integration_tests.ml
@@ -564,7 +564,7 @@ let main = test_suite "Integration (End to End)" [
     (* test "guess the hash mligo" guess_the_hash_mligo ; WIP? *)
     (* test "failwith mligo" failwith_mligo ; *)
     (* test "guess string mligo" guess_string_mligo ; WIP? *)
-    (* test "lambda mligo" lambda_mligo ; *)
+    test "lambda mligo" lambda_mligo ;
     (* test "lambda2 mligo" lambda2_mligo ; *)
     test "website1 ligo" website1_ligo ;
     test "website2 ligo" website2_ligo ;
diff --git a/src/test/test_helpers.ml b/src/test/test_helpers.ml
index 57b8246f8..5817845aa 100644
--- a/src/test/test_helpers.ml
+++ b/src/test/test_helpers.ml
@@ -5,6 +5,35 @@ type test =
   | Test_suite of (string * test list)
   | Test of test_case
 
+let error_pp out (e : error) =
+    let open JSON_string_utils in
+  let message =
+    let opt = e |> member "message" |> string in
+    let msg = Option.unopt ~default:"" opt in
+    if msg = ""
+    then ""
+    else ": " ^ msg in
+  let error_code =
+    let error_code = e |> member "error_code" in
+    match error_code with
+    | `Null -> ""
+    | _ -> " (" ^ (J.to_string error_code) ^ ")" in
+  let title =
+    let opt = e |> member "title" |> string in
+    Option.unopt ~default:"" opt in
+  let data =
+    let data = e |> member "data" in
+    match data with
+    | `Null -> ""
+    | _ -> " " ^ (J.to_string data) ^ "\n" in
+  let infos =
+    let infos = e |> member "infos" in
+    match infos with
+    | `Null -> ""
+    | _ -> " " ^ (J.to_string infos) ^ "\n" in
+  Format.fprintf out "%s%s%s.\n%s%s" title error_code message data infos
+
+
 let test name f =
   Test (
     Alcotest.test_case name `Quick @@ fun () ->

From 743098ecbddd2e2a99978eb8945cea22879987cc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Fri, 7 Jun 2019 01:17:33 +0200
Subject: [PATCH 17/19] added test calling a function with ligo

---
 src/contracts/lambda.ligo                   | 6 ++++++
 src/contracts/parser-bad-reported-term.ligo | 6 ++++++
 src/test/integration_tests.ml               | 7 +++++++
 3 files changed, 19 insertions(+)
 create mode 100644 src/contracts/lambda.ligo
 create mode 100644 src/contracts/parser-bad-reported-term.ligo

diff --git a/src/contracts/lambda.ligo b/src/contracts/lambda.ligo
new file mode 100644
index 000000000..cc426e83d
--- /dev/null
+++ b/src/contracts/lambda.ligo
@@ -0,0 +1,6 @@
+function f (const x : unit) : unit is
+  begin skip end with unit
+
+function main (const p : unit ; const s : unit) : unit is
+  var y : unit := f(unit) ;
+  begin skip end with y
diff --git a/src/contracts/parser-bad-reported-term.ligo b/src/contracts/parser-bad-reported-term.ligo
new file mode 100644
index 000000000..05dc69e3e
--- /dev/null
+++ b/src/contracts/parser-bad-reported-term.ligo
@@ -0,0 +1,6 @@
+function f (const x : unit) : unit is
+  begin skip end with unit
+
+function main (const p : unit ; const s : unit) : unit is
+  behin skip end with f unit
+// the srcloc is correct but the reported term is "skip" instead of "behin".
diff --git a/src/test/integration_tests.ml b/src/test/integration_tests.ml
index ba9db500c..94616fef6 100644
--- a/src/test/integration_tests.ml
+++ b/src/test/integration_tests.ml
@@ -500,6 +500,12 @@ let lambda_mligo () : unit result =
   let make_expected = (e_unit ()) in
   expect_eq program "main" make_input make_expected
 
+let lambda_ligo () : unit result =
+  let%bind program = type_file "./contracts/lambda.ligo" in
+  let make_input = e_pair (e_unit ()) (e_unit ()) in
+  let make_expected = (e_unit ()) in
+  expect_eq program "main" make_input make_expected
+
 let lambda2_mligo () : unit result =
   let%bind program = mtype_file "./contracts/lambda2.mligo" in
   let make_input = e_pair (e_unit ()) (e_unit ()) in
@@ -565,6 +571,7 @@ let main = test_suite "Integration (End to End)" [
     (* test "failwith mligo" failwith_mligo ; *)
     (* test "guess string mligo" guess_string_mligo ; WIP? *)
     test "lambda mligo" lambda_mligo ;
+    test "lambda ligo" lambda_ligo ;
     (* test "lambda2 mligo" lambda2_mligo ; *)
     test "website1 ligo" website1_ligo ;
     test "website2 ligo" website2_ligo ;

From a8e344c24ea9298e099177f69cbc2c44771bf046 Mon Sep 17 00:00:00 2001
From: Christian Rinderknecht <Christian.Rinderknecht@tezcore.com>
Date: Fri, 7 Jun 2019 12:48:21 +0200
Subject: [PATCH 18/19] Added test for Matej.

---
 src/contracts/match_bis.mligo | 20 ++++++++++++++++++++
 src/test/integration_tests.ml |  9 +++++++++
 2 files changed, 29 insertions(+)
 create mode 100644 src/contracts/match_bis.mligo

diff --git a/src/contracts/match_bis.mligo b/src/contracts/match_bis.mligo
new file mode 100644
index 000000000..3f4e02c23
--- /dev/null
+++ b/src/contracts/match_bis.mligo
@@ -0,0 +1,20 @@
+type storage = int
+
+(* variant defining pseudo multi-entrypoint actions *)
+
+type action =
+| Increment of int
+| Decrement of int
+
+let add (a: int) (b: int) : int = a + b
+
+let subtract (a: int) (b: int) : int = a - b
+
+(* real entrypoint that re-routes the flow based on the action provided *)
+
+let%entry main (p : action) storage =
+  let storage =
+    match p with
+    | Increment n -> add storage n
+    | Decrement n -> subtract storage n
+  in (([] : operation list), storage)
diff --git a/src/test/integration_tests.ml b/src/test/integration_tests.ml
index ba9db500c..fcaea7093 100644
--- a/src/test/integration_tests.ml
+++ b/src/test/integration_tests.ml
@@ -484,6 +484,14 @@ let match_variant () : unit result =
     e_pair (e_typed_list [] t_operation) (e_int (3-n))
   in expect_eq_n program "main" make_input make_expected
 
+let match_matej () : unit result =
+  let%bind program = mtype_file "./contracts/match_bis.mligo" in
+  let make_input n =
+    e_pair (e_constructor "Decrement" (e_int n)) (e_int 3) in
+  let make_expected n =
+    e_pair (e_typed_list [] t_operation) (e_int (3-n))
+  in expect_eq_n program "main" make_input make_expected
+
 let mligo_list () : unit result =
   let%bind program = mtype_file "./contracts/list.mligo" in
   let make_input n =
@@ -560,6 +568,7 @@ let main = test_suite "Integration (End to End)" [
     test "counter contract (mligo)" counter_mligo ;
     test "let-in (mligo)" let_in_mligo ;
     test "match variant (mligo)" match_variant ;
+    test "match variant 2 (mligo)" match_matej ;
     (* test "list matching (mligo)" mligo_list ; *)
     (* test "guess the hash mligo" guess_the_hash_mligo ; WIP? *)
     (* test "failwith mligo" failwith_mligo ; *)

From b2ec459b08c2ff14e4f67e1cf44a09d8d58c5a3b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Georges=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Fri, 7 Jun 2019 15:16:24 +0200
Subject: [PATCH 19/19] Added types for mligo map instructions

---
 src/ast_simplified/combinators.ml |  2 +-
 src/operators/operators.ml        | 58 +++++++++++++++++++++++++++++--
 src/simplify/pascaligo.ml         |  2 +-
 3 files changed, 58 insertions(+), 4 deletions(-)

diff --git a/src/ast_simplified/combinators.ml b/src/ast_simplified/combinators.ml
index 654d55024..690c9dfcb 100644
--- a/src/ast_simplified/combinators.ml
+++ b/src/ast_simplified/combinators.ml
@@ -49,7 +49,7 @@ let e_record ?loc map : expression = Location.wrap ?loc @@ E_record map
 let e_tuple ?loc lst : expression = Location.wrap ?loc @@ E_tuple lst
 let e_some ?loc s : expression = Location.wrap ?loc @@ E_constant ("SOME", [s])
 let e_none ?loc () : expression = Location.wrap ?loc @@ E_constant ("NONE", [])
-let e_map_update ?loc k v old : expression = Location.wrap ?loc @@ E_constant ("MAP_UPDATE" , [k ; v ; old])
+let e_map_add ?loc k v old : expression = Location.wrap ?loc @@ E_constant ("MAP_ADD" , [k ; v ; old])
 let e_map ?loc lst : expression = Location.wrap ?loc @@ E_map lst
 let e_list ?loc lst : expression = Location.wrap ?loc @@ E_list lst
 let e_pair ?loc a b : expression = Location.wrap ?loc @@ E_tuple [a; b]
diff --git a/src/operators/operators.ml b/src/operators/operators.ml
index afb5d34af..d8c3d134f 100644
--- a/src/operators/operators.ml
+++ b/src/operators/operators.ml
@@ -189,12 +189,57 @@ module Typer = struct
     let%bind () = assert_type_value_eq (src , k) in
     ok m
 
-  let map_update : typer = typer_3 "MAP_UPDATE" @@ fun k v m ->
+  let map_add : typer = typer_3 "MAP_ADD" @@ fun k v m ->
     let%bind (src, dst) = get_t_map m in
     let%bind () = assert_type_value_eq (src, k) in
     let%bind () = assert_type_value_eq (dst, v) in
     ok m
 
+  let map_update : typer = typer_3 "MAP_UPDATE_TODO" @@ fun k v m ->
+    let%bind (src, dst) = get_t_map m in
+    let%bind () = assert_type_value_eq (src, k) in
+    let%bind v' = get_t_option v in
+    let%bind () = assert_type_value_eq (dst, v') in
+    ok m
+
+  let map_mem : typer = typer_2 "MAP_MEM_TODO" @@ fun k m ->
+    let%bind (src, _dst) = get_t_map m in
+    let%bind () = assert_type_value_eq (src, k) in
+    ok @@ t_bool ()
+
+  let map_find : typer = typer_2 "MAP_FIND_TODO" @@ fun k m ->
+    let%bind (src, dst) = get_t_map m in
+    let%bind () = assert_type_value_eq (src, k) in
+    ok @@ t_option dst ()
+
+  let map_fold : typer = typer_3 "MAP_FOLD_TODO" @@ fun f m acc ->
+    let%bind (src, dst) = get_t_map m in
+    let expected_f_type = t_function (t_tuple [(t_tuple [src ; dst] ()) ; acc] ()) acc () in
+    let%bind () = assert_type_value_eq (f, expected_f_type) in
+    ok @@ acc
+
+  let map_map : typer = typer_2 "MAP_MAP_TODO" @@ fun f m ->
+    let%bind (k, v) = get_t_map m in
+    let%bind (input_type, result_type) = get_t_function f in
+    let%bind () = assert_type_value_eq (input_type, t_tuple [k ; v] ()) in
+    ok @@ t_map k result_type ()
+
+  let map_map_fold : typer = typer_3 "MAP_MAP_TODO" @@ fun f m acc ->
+    let%bind (k, v) = get_t_map m in
+    let%bind (input_type, result_type) = get_t_function f in
+    let%bind () = assert_type_value_eq (input_type, t_tuple [t_tuple [k ; v] () ; acc] ()) in
+    let%bind ttuple = get_t_tuple result_type in
+    match ttuple with
+    | [result_acc ; result_dst ] ->
+      ok @@ t_tuple [ t_map k result_dst () ; result_acc ] ()
+    (* TODO: error message *)
+    | _ -> fail @@ simple_error "function passed to map should take (k * v) * acc as an argument"
+
+  let map_iter : typer = typer_2 "MAP_MAP_TODO" @@ fun f m ->
+    let%bind (k, v) = get_t_map m in
+    let%bind () = assert_type_value_eq (f, t_function (t_tuple [k ; v] ()) (t_unit ()) ()) in
+    ok @@ t_unit ()
+
   let size = typer_1 "SIZE" @@ fun t ->
     let%bind () =
       Assert.assert_true @@
@@ -307,7 +352,15 @@ module Typer = struct
       boolean_operator_2 "OR" ;
       boolean_operator_2 "AND" ;
       map_remove ;
+      map_add ;
       map_update ;
+      map_mem ;
+      map_find ;
+      map_map_fold ;
+      map_map ;
+      map_fold ;
+      map_iter ;
+      (* map_size ; (* use size *) *)
       int ;
       size ;
       failwith_ ;
@@ -379,7 +432,8 @@ module Compiler = struct
     ("CALL" , simple_ternary @@ prim I_TRANSFER_TOKENS) ;
     ("SOURCE" , simple_constant @@ prim I_SOURCE) ;
     ("SENDER" , simple_constant @@ prim I_SENDER) ;
-    ( "MAP_UPDATE" , simple_ternary @@ seq [dip (i_some) ; prim I_UPDATE ]) ;
+    ( "MAP_ADD" , simple_ternary @@ seq [dip (i_some) ; prim I_UPDATE ]) ;
+    ( "MAP_UPDATE" , simple_ternary @@ prim I_UPDATE) ;
   ]
 
 end
diff --git a/src/simplify/pascaligo.ml b/src/simplify/pascaligo.ml
index 58b5d6896..53e004688 100644
--- a/src/simplify/pascaligo.ml
+++ b/src/simplify/pascaligo.ml
@@ -765,7 +765,7 @@ and simpl_single_instruction : Raw.single_instr -> (_ -> expression result) resu
               | _ -> fail @@ unsupported_deep_map_assign v in
             let%bind key_expr = simpl_expression v'.index.value.inside in
             let old_expr = e_variable name.value in
-            let expr' = e_map_update key_expr value_expr old_expr in
+            let expr' = e_map_add key_expr value_expr old_expr in
             return @@ e_assign ~loc name.value [] expr'
           )
     )