From c5aab2cf85d4722c674b2ec07373f396ffd75e4f Mon Sep 17 00:00:00 2001
From: Galfour <gabriel.alfour@gmail.com>
Date: Sun, 5 May 2019 13:05:32 +0000
Subject: [PATCH] close to finishing

---
 src/lib_utils/PP.ml                       |   1 +
 src/lib_utils/trace.ml                    |  10 ++
 src/lib_utils/x_list.ml                   |  18 ++-
 src/lib_utils/x_tezos_micheline.ml        |   6 +-
 src/ligo/compiler/compiler_environment.ml | 127 ++++++++++++++++++++--
 src/ligo/compiler/compiler_program.ml     | 104 +++++++++---------
 src/ligo/compiler/compiler_type.ml        |   4 +-
 src/ligo/contracts/tuple.ligo             |  20 ++--
 src/ligo/mini_c/combinators.ml            |   3 +
 src/ligo/mini_c/environment.ml            |  16 +++
 src/ligo/test/integration_tests.ml        |  23 ++--
 src/ligo/transpiler/transpiler.ml         |  72 ++++++------
 12 files changed, 283 insertions(+), 121 deletions(-)

diff --git a/src/lib_utils/PP.ml b/src/lib_utils/PP.ml
index 49063c2d4..ab9a5b422 100644
--- a/src/lib_utils/PP.ml
+++ b/src/lib_utils/PP.ml
@@ -2,6 +2,7 @@ open Format
 let string : formatter -> string -> unit = fun ppf s -> fprintf ppf "%s" s
 let tag tag : formatter -> unit -> unit = fun ppf () -> fprintf ppf tag
 let bool ppf b = fprintf ppf "%b" b
+let pair f g ppf (a , b) = fprintf ppf "%a , %a" f a g b
 let new_line : formatter -> unit -> unit = tag "@;"
 let rec new_lines n ppf () =
   match n with
diff --git a/src/lib_utils/trace.ml b/src/lib_utils/trace.ml
index 29686875b..cc51ac242 100644
--- a/src/lib_utils/trace.ml
+++ b/src/lib_utils/trace.ml
@@ -189,6 +189,16 @@ let bind_fold_map_list = fun f acc lst ->
   aux (acc , []) f lst >>? fun (_acc' , lst') ->
   ok @@ List.rev lst'
 
+let bind_fold_map_right_list = fun f acc lst ->
+  let rec aux (acc , prev) f = function
+    | [] -> ok (acc , prev)
+    | hd :: tl ->
+        f acc hd >>? fun (acc' , hd') ->
+        aux (acc' , hd' :: prev) f tl
+  in
+  aux (acc , []) f (List.rev lst) >>? fun (_acc' , lst') ->
+  ok lst'
+
 let bind_fold_right_list f init lst =
   let aux x y =
     x >>? fun x ->
diff --git a/src/lib_utils/x_list.ml b/src/lib_utils/x_list.ml
index 2c28dd98f..71d317810 100644
--- a/src/lib_utils/x_list.ml
+++ b/src/lib_utils/x_list.ml
@@ -7,7 +7,7 @@ let map ?(acc = []) f lst =
   in
   aux acc f (List.rev lst)
 
-let fold_map : type acc ele ret . (acc -> ele -> (acc * ret)) -> acc -> ele list -> ret list =
+let fold_map_right : type acc ele ret . (acc -> ele -> (acc * ret)) -> acc -> ele list -> ret list =
   fun f acc lst ->
   let rec aux (acc , prev) f = function
     | [] -> (acc , prev)
@@ -17,8 +17,24 @@ let fold_map : type acc ele ret . (acc -> ele -> (acc * ret)) -> acc -> ele list
   in
   snd @@ aux (acc , []) f (List.rev lst)
 
+let fold_map : type acc ele ret . (acc -> ele -> (acc * ret)) -> acc -> ele list -> ret list =
+  fun f acc lst ->
+  let rec aux (acc , prev) f = function
+    | [] -> (acc , prev)
+    | hd :: tl ->
+        let (acc' , hd') = f acc hd in
+        aux (acc' , hd' :: prev) f tl
+  in
+  List.rev @@ snd @@ aux (acc , []) f lst
+
 let fold_right' f init lst = List.fold_left f init (List.rev lst)
 
+let rec remove_element x lst =
+  match lst with
+  | [] -> raise (Failure "X_list.remove_element")
+  | hd :: tl when x = hd -> tl
+  | hd :: tl -> hd :: remove_element x tl
+
 let filter_map f =
   let rec aux acc lst = match lst with
     | [] -> List.rev acc
diff --git a/src/lib_utils/x_tezos_micheline.ml b/src/lib_utils/x_tezos_micheline.ml
index b84abc1e0..61c8660bc 100644
--- a/src/lib_utils/x_tezos_micheline.ml
+++ b/src/lib_utils/x_tezos_micheline.ml
@@ -54,9 +54,9 @@ module Michelson = struct
   let i_drop = prim I_DROP
   let i_exec = prim I_EXEC
 
-  let i_if a b = prim ~children:[a;b] I_IF
-  let i_if_none a b = prim ~children:[a;b] I_IF_NONE
-  let i_if_left a b = prim ~children:[a;b] I_IF_LEFT
+  let i_if a b = prim ~children:[seq [a] ; seq[b]] I_IF
+  let i_if_none a b = prim ~children:[seq [a] ; seq[b]] I_IF_NONE
+  let i_if_left a b = prim ~children:[seq [a] ; seq[b]] I_IF_LEFT
   let i_failwith = prim I_FAILWITH
   let i_assert_some = i_if_none (seq [i_push_string "ASSERT_SOME" ; i_failwith]) (seq [])
   let i_assert_some_msg msg = i_if_none (seq [msg ; i_failwith]) (seq [])
diff --git a/src/ligo/compiler/compiler_environment.ml b/src/ligo/compiler/compiler_environment.ml
index 0328d5859..2f99d0a5b 100644
--- a/src/ligo/compiler/compiler_environment.ml
+++ b/src/ligo/compiler/compiler_environment.ml
@@ -87,22 +87,44 @@ let add : environment -> (string * type_value) -> michelson result = fun e (_s ,
   ok code
 
 let select : environment -> string list -> michelson result = fun e lst ->
+  let module L = Logger.Stateful() in
+  let e_lst =
+    let e_lst = Environment.to_list e in
+    let aux selector (s , _) =
+      L.log @@ Format.asprintf "Selector : %a\n" PP_helpers.(list_sep string (const " , ")) selector ;
+      match List.mem s selector with
+      | true -> List.remove_element s selector , true
+      | false -> selector , false in
+    let e_lst' = List.fold_map_right aux lst e_lst in
+    let e_lst'' = List.combine e_lst e_lst' in
+    e_lst'' in
   let code =
-    let aux = fun acc (s , _) ->
-      seq [
-        dip acc ;
-        if List.mem s lst
-        then seq []
-        else i_drop ;
-      ]
+    let aux = fun code (_ , b) ->
+      match b with
+      | false -> seq [dip code ; i_drop]
+      | true -> dip code
     in
-    Environment.fold aux (seq []) e in
+    List.fold_right' aux (seq []) e_lst in
 
   let%bind () =
-    let error () = ok @@ simple_error "error producing Env.select" in
     let%bind (Stack.Ex_stack_ty input_stack_ty) = Compiler_type.Ty.environment e in
-    let e' = Environment.filter (fun (s , _) -> List.mem s lst) e in
+    let e' =
+      Environment.of_list
+      @@ List.map fst
+      @@ List.filter snd
+      @@ e_lst
+    in
     let%bind (Stack.Ex_stack_ty output_stack_ty) = Compiler_type.Ty.environment e' in
+    let error () =
+      let title () = "error producing Env.select" in
+      let content () = Format.asprintf "\nInput : %a\nOutput : %a\nList : {%a}\nCode : %a\nLog : %s\n"
+          PP.environment e
+          PP.environment e'
+          PP_helpers.(list_sep (pair PP.environment_element bool) (const " || ")) e_lst
+          Micheline.Michelson.pp code
+          (L.get ())
+      in
+      ok @@ (error title content) in
     let%bind _ =
       Trace.trace_tzresult_lwt_r error @@
       Memory_proto_alpha.parse_michelson code
@@ -117,3 +139,88 @@ let clear : environment -> michelson result = fun e -> select e []
 let select_env : environment -> environment -> michelson result = fun e e' ->
   let lst = Environment.get_names e' in
   select e lst
+
+let pack : environment -> michelson result = fun e ->
+  let%bind () =
+    trace_strong (simple_error "pack empty env") @@
+    Assert.assert_true (List.length e <> 0) in
+  ok @@ seq @@ List.map (Function.constant i_pair) @@ List.tl e
+
+let unpack : environment -> michelson result = fun e ->
+  let%bind () =
+    trace_strong (simple_error "unpack empty env") @@
+    Assert.assert_true (List.length e <> 0) in
+  ok @@ seq @@ List.map (Function.constant i_unpair) @@ List.tl e
+
+let pack_select : environment -> string list -> michelson result = fun e lst ->
+  let module L = Logger.Stateful() in
+  let e_lst =
+    let e_lst = Environment.to_list e in
+    let aux selector (s , _) =
+      L.log @@ Format.asprintf "Selector : %a\n" PP_helpers.(list_sep string (const " , ")) selector ;
+      match List.mem s selector with
+      | true -> List.remove_element s selector , true
+      | false -> selector , false in
+    let e_lst' = List.fold_map_right aux lst e_lst in
+    let e_lst'' = List.combine e_lst e_lst' in
+    e_lst'' in
+  let (_ , code) =
+    let aux = fun (first , code) (_ , b) ->
+      match b with
+      | false -> (first , seq [dip code ; i_swap])
+      | true -> (false ,
+                 match first with
+                 | true -> i_dup
+                 | false -> seq [dip code ; i_dup ; dip i_pair ; i_swap]
+                )
+    in
+    List.fold_right' aux (true , seq []) e_lst in
+
+  let%bind () =
+    let%bind (Stack.Ex_stack_ty input_stack_ty) = Compiler_type.Ty.environment e in
+    let e' =
+      Environment.of_list
+      @@ List.map fst
+      @@ List.filter snd
+      @@ e_lst
+    in
+    let%bind (Ex_ty output_ty) = Compiler_type.Ty.environment_representation e' in
+    let output_stack_ty = Stack.(output_ty @: input_stack_ty) in
+    let error () =
+      let title () = "error producing Env.pack_select" in
+      let content () = Format.asprintf "\nInput : %a\nOutput : %a\nList : {%a}\nCode : %a\nLog : %s\n"
+          PP.environment e
+          PP.environment e'
+          PP_helpers.(list_sep (pair PP.environment_element bool) (const " || ")) e_lst
+          Micheline.Michelson.pp code
+          (L.get ())
+      in
+      ok @@ (error title content) in
+    let%bind _ =
+      Trace.trace_tzresult_lwt_r error @@
+      Memory_proto_alpha.parse_michelson code
+        input_stack_ty output_stack_ty in
+    ok ()
+  in
+
+  ok code
+
+let add_packed_anon : environment -> type_value -> michelson result = fun e type_value ->
+  let code = i_pair in
+
+  let%bind () =
+    let error () = ok @@ simple_error "error producing Env.get" in
+    let%bind (Ex_ty input_ty) = Compiler_type.Ty.environment_representation e in
+    let e' = Environment.add ("_add_packed_anon" , type_value) e in
+    let%bind (Ex_ty output_ty) = Compiler_type.Ty.environment_representation e' in
+    let%bind (Ex_ty ty) = Compiler_type.Ty.type_ type_value in
+    let input_stack_ty = Stack.(ty @: input_ty @: nil) in
+    let output_stack_ty = Stack.(output_ty @: nil) in
+    let%bind _ =
+      Trace.trace_tzresult_lwt_r error @@
+      Memory_proto_alpha.parse_michelson code
+        input_stack_ty output_stack_ty in
+    ok ()
+  in
+
+  ok code
diff --git a/src/ligo/compiler/compiler_program.ml b/src/ligo/compiler/compiler_program.ml
index 045428ddc..cbaf01ce0 100644
--- a/src/ligo/compiler/compiler_program.ml
+++ b/src/ligo/compiler/compiler_program.ml
@@ -71,17 +71,16 @@ and translate_function (content:anon_function) : michelson result =
   ok @@ seq [ body ]
 
 and translate_expression ?(first=false) (expr:expression) (env:environment) : (michelson * environment) result =
-  let (expr' , ty , _) = Combinators.Expression.(get_content expr , get_type expr , get_environment expr) in
+  let (expr' , ty) = Combinators.Expression.(get_content expr , get_type expr) in
   let error_message () = Format.asprintf  "%a" PP.expression expr in
 
-  let return code =
+  let return ?env' code =
+    let env' =
+      let default = env in
+      Environment.add ("_tmp_expression" , ty) @@ Option.unopt ~default env' in
     let%bind (Stack.Ex_stack_ty input_stack_ty) = Compiler_type.Ty.environment env in
     let%bind output_type = Compiler_type.type_ ty in
-    let%bind (Ex_ty output_ty) =
-      let error_message () = Format.asprintf "%a" Michelson.pp output_type in
-      Trace.trace_tzresult_lwt (fun () -> error (thunk "error parsing output ty") error_message ()) @@
-      Tezos_utils.Memory_proto_alpha.parse_michelson_ty output_type in
-    let output_stack_ty = Stack.(output_ty @: input_stack_ty) in
+    let%bind (Stack.Ex_stack_ty output_stack_ty) = Compiler_type.Ty.environment env' in
     let error_message () =
       let%bind schema_michelsons = Compiler_type.environment env in
       ok @@ Format.asprintf
@@ -101,13 +100,14 @@ and translate_expression ?(first=false) (expr:expression) (env:environment) : (m
       Tezos_utils.Memory_proto_alpha.parse_michelson code
         input_stack_ty output_stack_ty
     in
-    let env' = Environment.add ("_tmp_expression" , ty) env in
     ok (code , env')
   in
 
   trace (error (thunk "compiling expression") error_message) @@
   match expr' with
-  | E_capture_environment _c -> simple_fail "capture"
+  | E_capture_environment c ->
+      let%bind code = Compiler_environment.pack_select env c in
+      return @@ code
   | E_literal v ->
       let%bind v = translate_value v in
       let%bind t = Compiler_type.type_ ty in
@@ -127,10 +127,11 @@ and translate_expression ?(first=false) (expr:expression) (env:environment) : (m
             prim I_EXEC ;
           ]
         )
-      | T_deep_closure (_small_env, _, _) -> (
+      | T_deep_closure (small_env, input_ty , _) -> (
           trace (simple_error "Compiling deep closure application") @@
-          let%bind (f' , env') = translate_expression ~first f env in
-          let%bind (arg' , _) = translate_expression arg env' in
+          let%bind (arg' , env') = translate_expression arg env in
+          let%bind (f' , _) = translate_expression f env' in
+          let%bind append_closure = Compiler_environment.add_packed_anon small_env input_ty in
           let error =
             let error_title () = "michelson type-checking closure application" in
             let error_content () =
@@ -143,14 +144,10 @@ and translate_expression ?(first=false) (expr:expression) (env:environment) : (m
           in
           trace error @@
           return @@ seq [
-            i_comment "(* unit :: env *)" ;
-            i_comment "compute arg" ;
             arg' ;
-            i_comment "(* (arg * unit) :: env *)" ;
-            i_comment "compute closure" ;
-            dip @@ seq [f' ; i_unpair] ;
-            i_comment "(* arg :: capture :: f :: unit :: env *)" ;
-            i_exec ; (* output :: stack :: env *)
+            f' ; i_unpair ;
+            dip @@ append_closure ;
+            i_swap ; i_exec ;
           ]
         )
       | _ -> simple_fail "E_applicationing something not appliable"
@@ -169,19 +166,24 @@ and translate_expression ?(first=false) (expr:expression) (env:environment) : (m
             PP.environment env ;
           ok (env' , code)
         in
-        bind_fold_map_list aux env lst in
+        bind_fold_map_right_list aux env lst in
       let%bind predicate = get_predicate str ty lst in
+      let pre_code = seq @@ List.rev lst' in
       let%bind code = match (predicate, List.length lst) with
-        | Constant c, 0 -> ok @@ seq @@ lst' @ [
+        | Constant c, 0 -> ok @@ seq [
+            pre_code ;
             c ;
           ]
-        | Unary f, 1 -> ok @@ seq @@ lst' @ [
+        | Unary f, 1 -> ok @@ seq [
+            pre_code ;
             f ;
           ]
-        | Binary f, 2 -> ok @@ seq @@ lst' @ [
+        | Binary f, 2 -> ok @@ seq [
+            pre_code ;
             f ;
           ]
-        | Ternary f, 3 -> ok @@ seq @@ lst' @ [
+        | Ternary f, 3 -> ok @@ seq [
+            pre_code ;
             f ;
           ]
         | _ -> simple_fail "bad arity"
@@ -207,20 +209,21 @@ and translate_expression ?(first=false) (expr:expression) (env:environment) : (m
       let%bind (a' , _) = translate_expression a env' in
       let%bind (b' , _) = translate_expression b env' in
       let%bind code = ok (seq [
-          c' ; i_unpair ;
+          c' ;
           i_if a' b' ;
         ]) in
       return code
     )
   | E_if_none (c, n, (_ , s)) -> (
-      let%bind (c' , env') = translate_expression c env in
-      let%bind (n' , _) = translate_expression n env' in
-      let%bind (s' , _) = translate_expression s env' in
+      let%bind (c' , _env') = translate_expression c env in
+      let%bind (n' , _) = translate_expression n n.environment in
+      let%bind (s' , _) = translate_expression s s.environment in
+      let%bind restrict_s = Compiler_environment.select_env s.environment env in
       let%bind code = ok (seq [
-          c' ; i_unpair ;
+          c' ;
           i_if_none n' (seq [
-              i_pair ;
               s' ;
+              restrict_s ;
             ])
           ;
         ]) in
@@ -229,18 +232,16 @@ and translate_expression ?(first=false) (expr:expression) (env:environment) : (m
   | E_if_left (c, (_ , l), (_ , r)) -> (
       let%bind (c' , _env') = translate_expression c env in
       let%bind (l' , _) = translate_expression l l.environment in
-      let%bind (r' , _) = translate_expression r l.environment in
+      let%bind (r' , _) = translate_expression r r.environment in
       let%bind restrict_l = Compiler_environment.select_env l.environment env in
       let%bind restrict_r = Compiler_environment.select_env r.environment env in
       let%bind code = ok (seq [
-          c' ; i_unpair ;
+          c' ;
           i_if_left (seq [
-              i_swap ; dip i_pair ;
               l' ;
               i_comment "restrict left" ;
               dip restrict_l ;
             ]) (seq [
-              i_swap ; dip i_pair ;
               r' ;
               i_comment "restrict right" ;
               dip restrict_r ;
@@ -292,12 +293,18 @@ and translate_statement ((s', w_env) as s:statement) : michelson result =
   trace (fun () -> error (thunk "compiling statement") error_message ()) @@ match s' with
   | S_environment_add _ ->
       simple_fail "add not ready yet"
-  | S_environment_select _ ->
-      simple_fail "select not ready yet"
-  | S_environment_load _ ->
-      simple_fail "load not ready yet"
-  (* | S_environment_add (name, tv) ->
-   *     Environment.to_michelson_add (name, tv) w_env.pre_environment *)
+  | S_environment_select sub_env ->
+      let%bind code = Compiler_environment.select_env w_env.pre_environment sub_env in
+      return code
+  | S_environment_load (expr , env) ->
+      let%bind (expr' , _) = translate_expression expr w_env.pre_environment in
+      let%bind clear = Compiler_environment.select w_env.pre_environment [] in
+      let%bind unpack = Compiler_environment.unpack env in
+      return @@ seq [
+        expr' ;
+        dip clear ;
+        unpack ;
+      ]
   | S_declaration (s, expr) ->
       let tv = Combinators.Expression.get_type expr in
       let%bind (expr , _) = translate_expression expr w_env.pre_environment in
@@ -332,9 +339,7 @@ and translate_statement ((s', w_env) as s:statement) : michelson result =
       let%bind a' = translate_regular_block a in
       let%bind b' = translate_regular_block b in
       return @@ seq [
-        i_push_unit ;
         expr ;
-        prim I_CAR ;
         prim ~children:[seq [a'];seq [b']] I_IF ;
       ]
   | S_do expr -> (
@@ -361,11 +366,12 @@ and translate_statement ((s', w_env) as s:statement) : michelson result =
       let%bind add =
         let env' = w_env.pre_environment in
         Compiler_environment.add env' (name, tv) in
+      let%bind restrict_s = Compiler_environment.select_env (snd some).post_environment w_env.pre_environment in
       return @@ seq [
-        i_push_unit ; expr ; i_car ;
+        expr ;
         prim ~children:[
           seq [none'] ;
-          seq [add ; some'] ;
+          seq [add ; some' ; restrict_s] ;
         ] I_IF_NONE
       ]
   | S_while (expr, block) ->
@@ -375,15 +381,15 @@ and translate_statement ((s', w_env) as s:statement) : michelson result =
         let env_while = (snd block).pre_environment in
         Compiler_environment.select_env (snd block).post_environment env_while in
       return @@ seq [
-        i_push_unit ; expr ; i_car ;
+        expr ;
         prim ~children:[seq [
             block' ;
             restrict_block ;
-            i_push_unit ; expr ; i_car]] I_LOOP ;
+            expr]] I_LOOP ;
       ]
   | S_patch (name, lrs, expr) ->
-      let%bind (expr' , _) = translate_expression expr w_env.pre_environment in
-      let%bind get_code = Compiler_environment.get w_env.pre_environment name in
+      let%bind (expr' , env') = translate_expression expr w_env.pre_environment in
+      let%bind get_code = Compiler_environment.get env' name in
       let modify_code =
         let aux acc step = match step with
           | `Left -> seq [dip i_unpair ; acc ; i_pair]
@@ -407,7 +413,7 @@ and translate_statement ((s', w_env) as s:statement) : michelson result =
       return @@ seq [
         expr' ;
         get_code ;
-        modify_code ;
+        i_swap ; modify_code ;
         set_code ;
       ]
 
diff --git a/src/ligo/compiler/compiler_type.ml b/src/ligo/compiler/compiler_type.ml
index ed7c2cfa3..ad4849242 100644
--- a/src/ligo/compiler/compiler_type.ml
+++ b/src/ligo/compiler/compiler_type.ml
@@ -71,7 +71,7 @@ module Ty = struct
         let%bind (Ex_ty capture) = environment_representation c in
         let%bind (Ex_ty arg) = type_ arg in
         let%bind (Ex_ty ret) = type_ ret in
-        ok @@ Ex_ty Contract_types.(pair capture @@ lambda (pair arg capture) ret)
+        ok @@ Ex_ty Contract_types.(pair (lambda (pair arg capture) ret) capture)
     | T_map (k, v) ->
         let%bind (Ex_comparable_ty k') = comparable_type k in
         let%bind (Ex_ty v') = type_ v in
@@ -146,7 +146,7 @@ let rec type_ : type_value -> O.michelson result =
       let%bind capture = environment_closure c in
       let%bind arg = type_ arg in
       let%bind ret = type_ ret in
-      ok @@ O.t_pair capture (O.t_lambda (O.t_pair arg capture) ret)
+      ok @@ O.t_pair (O.t_lambda (O.t_pair arg capture) ret) capture
 
 and environment_element (name, tyv) =
   let%bind michelson_type = type_ tyv in
diff --git a/src/ligo/contracts/tuple.ligo b/src/ligo/contracts/tuple.ligo
index aebdc7b87..9a39cde03 100644
--- a/src/ligo/contracts/tuple.ligo
+++ b/src/ligo/contracts/tuple.ligo
@@ -1,3 +1,13 @@
+type abc is (int * int * int)
+
+function projection_abc (const tpl : abc) : int is
+  block { skip } with tpl.1
+
+function modify_abc (const tpl : abc) : abc is
+  block {
+    tpl.1 := 2048 ;
+  } with tpl
+
 type foobar is (int * int)
 
 const fb : foobar = (0, 0)
@@ -10,13 +20,3 @@ function projection (const tpl : foobar) : int is
 type big_tuple is (int * int * int * int * int)
 
 const br : big_tuple = (23, 23, 23, 23, 23)
-
-type abc is (int * int * int)
-
-function projection_abc (const tpl : abc) : int is
-  block { skip } with tpl.1
-
-function modify_abc (const tpl : abc) : abc is
-  block {
-    tpl.1 := 2048 ;
-  } with tpl
diff --git a/src/ligo/mini_c/combinators.ml b/src/ligo/mini_c/combinators.ml
index 138c90d40..3ae362bd3 100644
--- a/src/ligo/mini_c/combinators.ml
+++ b/src/ligo/mini_c/combinators.ml
@@ -23,6 +23,9 @@ module Expression = struct
     environment = env ;
     is_toplevel = itl ;
   }
+
+  let pair : t -> t -> t' = fun a b -> E_constant ("PAIR" , [ a ; b ])
+
 end
 
 let get_bool (v:value) = match v with
diff --git a/src/ligo/mini_c/environment.ml b/src/ligo/mini_c/environment.ml
index 3d263a036..8b06cfa67 100644
--- a/src/ligo/mini_c/environment.ml
+++ b/src/ligo/mini_c/environment.ml
@@ -30,6 +30,22 @@ module Environment (* : ENVIRONMENT *) = struct
   let of_list : element list -> t = fun x -> x
   let to_list : t -> element list = fun x -> x
   let get_names : t -> string list = List.map fst
+  let remove : int -> t -> t = List.remove
+
+  let select : string list -> t -> t = fun lst env ->
+    let e_lst =
+      let e_lst = to_list env in
+      let aux selector (s , _) =
+        match List.mem s selector with
+        | true -> List.remove_element s selector , true
+        | false -> selector , false in
+      let e_lst' = List.fold_map_right aux lst e_lst in
+      let e_lst'' = List.combine e_lst e_lst' in
+      e_lst'' in
+    of_list
+    @@ List.map fst
+    @@ List.filter snd
+    @@ e_lst
 
 
   let fold : _ -> 'a -> t -> 'a = List.fold_left
diff --git a/src/ligo/test/integration_tests.ml b/src/ligo/test/integration_tests.ml
index c32055762..c8e26f363 100644
--- a/src/ligo/test/integration_tests.ml
+++ b/src/ligo/test/integration_tests.ml
@@ -38,6 +38,7 @@ let variant_matching () : unit result =
   let%bind () =
     let make_input = fun n -> e_a_constructor "Foo" (e_a_int n) in
     let make_expected = e_a_int in
+    expect program "fb" (make_input 0) (make_expected 0) >>? fun () ->
     expect_n program "fb" make_input make_expected >>? fun () ->
     expect program "fb" (e_a_constructor "Kee" (e_a_nat 50)) (e_a_int 23) >>? fun () ->
     expect program "fb" (e_a_constructor "Bar" (e_a_bool true)) (e_a_int 42) >>? fun () ->
@@ -69,13 +70,17 @@ let higher_order () : unit result =
 
 let shared_function () : unit result =
   let%bind program = type_file "./contracts/function-shared.ligo" in
+  (* let%bind () =
+   *   let make_expect = fun n -> (n + 1) in
+   *   expect_n_int program "inc" make_expect
+   * in
+   * let%bind () =
+   *   let make_expect = fun n -> (n + 2) in
+   *   expect_n_int program "double_inc" make_expect
+   * in *)
   let%bind () =
-    let make_expect = fun n -> (n + 1) in
-    expect_n_int program "inc" make_expect
-  in
-  let%bind () =
-    let make_expect = fun n -> (n + 2) in
-    expect_n_int program "double_inc" make_expect
+    let make_expect = fun n -> (2 * n + 3) in
+    expect program "foo" (e_a_int 0) (e_a_int @@ make_expect 0)
   in
   let%bind () =
     let make_expect = fun n -> (2 * n + 3) in
@@ -409,8 +414,7 @@ let main = "Integration (End to End)", [
     test "variant matching" variant_matching ;
     test "tuple" tuple ;
     test "record" record ;
-    test "closure" closure ;
-    test "shared function" shared_function ;
+    test "condition" condition ;
     test "shadow" shadow ;
     test "multiple parameters" multiple_parameters ;
     test "bool" bool_expression ;
@@ -419,7 +423,6 @@ let main = "Integration (End to End)", [
     test "option" option ;
     test "map" map ;
     test "list" list ;
-    test "condition" condition ;
     test "loop" loop ;
     test "matching" matching ;
     test "declarations" declarations ;
@@ -428,6 +431,8 @@ let main = "Integration (End to End)", [
     test "#include directives" include_ ;
     test "counter contract" counter_contract ;
     test "super counter contract" super_counter_contract ;
+    test "closure" closure ;
+    test "shared function" shared_function ;
     test "higher order" higher_order ;
     test "basic mligo" basic_mligo ;
     test "counter contract mligo" counter_mligo ;
diff --git a/src/ligo/transpiler/transpiler.ml b/src/ligo/transpiler/transpiler.ml
index 30261ba0a..2f86583d5 100644
--- a/src/ligo/transpiler/transpiler.ml
+++ b/src/ligo/transpiler/transpiler.ml
@@ -165,12 +165,11 @@ and translate_instruction (env:Environment.t) (i:AST.instruction) : statement li
       let env' = env in
       let return s =
         ok [ (s, environment_wrap env env) ] in
-      let restrict : block -> block = fun b -> Combinators.append_statement' b (S_environment_select env) in
       match m with
       | Match_bool {match_true ; match_false} -> (
           let%bind true_branch = translate_block env' match_true in
           let%bind false_branch = translate_block env' match_false in
-          return @@ S_cond (expr', restrict true_branch, restrict false_branch)
+          return @@ S_cond (expr', true_branch, false_branch)
         )
       | Match_option {match_none ; match_some = ((name, t), sm)} -> (
           let%bind none_branch = translate_block env' match_none in
@@ -179,7 +178,7 @@ and translate_instruction (env:Environment.t) (i:AST.instruction) : statement li
             let env'' = Environment.add (name, t') env' in
             translate_block env'' sm
           in
-          return @@ S_if_none (expr', restrict none_branch, ((name, t'), restrict some_branch))
+          return @@ S_if_none (expr', none_branch, ((name, t'), some_branch))
         )
       | _ -> simple_fail "todo : match"
     )
@@ -380,11 +379,7 @@ and translate_annotated_expression (env:Environment.t) (ae:AST.annotated_express
             in aux tree'
           in
 
-          let rec aux (acc , env) t =
-            let top =
-              match acc with
-              | None -> expr'
-              | Some x -> x in
+          let rec aux (top , env) t =
             match t with
             | ((`Leaf constructor_name) , tv) -> (
                 let%bind ((_ , name) , body) =
@@ -399,19 +394,19 @@ and translate_annotated_expression (env:Environment.t) (ae:AST.annotated_express
                   let%bind a_ty = get_t_left tv in
                   let a_var = "left" , a_ty in
                   let env' = Environment.(add a_var env) in
-                  let%bind e = aux ((Some (Expression.make (E_variable "left") a_ty env')) , env') a in
+                  let%bind e = aux (((Expression.make (E_variable "left") a_ty env')) , env') a in
                   ok (a_var , e)
                 in
                 let%bind b' =
                   let%bind b_ty = get_t_right tv in
                   let b_var = "right" , b_ty in
                   let env' = Environment.(add b_var env) in
-                  let%bind e = aux ((Some (Expression.make (E_variable "right") b_ty env')) , env') b in
+                  let%bind e = aux (((Expression.make (E_variable "right") b_ty env')) , env') b in
                   ok (b_var , e)
                 in
                 return ~env @@ E_if_left (top , a' , b')
           in
-          aux (None , env) tree''
+          aux (expr' , env) tree''
         )
       | AST.Match_list _ | AST.Match_tuple (_, _) ->
           simple_fail "only match bool and option exprs are translated yet"
@@ -419,32 +414,35 @@ and translate_annotated_expression (env:Environment.t) (ae:AST.annotated_express
 
 and translate_lambda_deep : Mini_c.Environment.t -> AST.lambda -> Mini_c.expression result = fun env l ->
   let { binder ; input_type ; output_type ; body ; result } : AST.lambda = l in
-  (* Deep capture. Capture the relevant part of the environment. Extend it with a new scope. Append it the input. *)
-  let%bind input_type' = translate_type input_type in
-  let%bind small_env =
-    let env' = env in
-    let new_env = Environment.add (binder, input_type') env' in
-    let free_variables = Ast_typed.Misc.Free_variables.lambda [] l in
-    let%bind elements =
-      let aux x =
-        let not_found_error =
-          let title () = "translate deep shallow (type checker didn't do its job)" in
-          let content () = Format.asprintf "%s in %a" x Mini_c.PP.environment new_env  in
-          error title content in
-        trace_option not_found_error @@
-        Environment.get_opt x new_env in
-      bind_map_list aux free_variables in
-    let kvs = List.combine free_variables elements in
-    let small_env = Environment.of_list kvs in
-    ok small_env
-  in
-  let new_env = Environment.(add (binder , input_type') small_env) in
-  let%bind (_, e) as body = translate_block new_env body in
-  let%bind result = translate_annotated_expression e.post_environment result in
-  let%bind output_type' = translate_type output_type in
-  let tv = Combinators.t_deep_closure small_env input_type' output_type' in
-  let content = D_function {binder;input=input_type';output=output_type';body;result} in
-  ok @@ Combinators.Expression.make_tpl (E_literal content, tv, env)
+  (* Deep capture. Capture the relevant part of the environment. *)
+  let%bind (fv , c_env , c_tv) =
+    let free_variables = Ast_typed.Free_variables.lambda [] l in
+    let sub_env = Mini_c.Environment.select free_variables env in
+    let tv = Environment.closure_representation sub_env in
+    ok (free_variables , sub_env , tv) in
+  let%bind (f_expr , input_tv , output_tv) =
+    let%bind raw_input = translate_type input_type in
+    let init_env = Environment.(add (binder , raw_input) c_env) in
+    let input = Environment.closure_representation init_env in
+    let%bind output = translate_type output_type in
+    let%bind (statements , body_env) = translate_block init_env body in
+    let body =
+      let load_env = Environment.(add ("closure_arg" , input) empty) in
+      let load_expr = Expression.make_tpl (E_variable "closure_arg" , input , load_env) in
+      let load_st = Mini_c.statement (S_environment_load (load_expr , init_env)) load_env in
+      let statements' = load_st :: statements in
+      (statements' , body_env)
+    in
+    let%bind result = translate_annotated_expression body_env.post_environment result in
+    let tv = Mini_c.t_function input output in
+    let f_literal = D_function { binder ; input ; output ; body ; result } in
+    let expr = Expression.make_tpl (E_literal f_literal , tv , env) in
+    ok (expr , raw_input , output) in
+  let%bind c_expr =
+    ok @@ Expression.make_tpl (E_capture_environment fv , c_tv , env) in
+  let expr = Expression.pair f_expr c_expr in
+  let tv = Mini_c.t_deep_closure c_env input_tv output_tv in
+  ok @@ Expression.make_tpl (expr , tv , env)
 
 and translate_lambda env l =
   let { binder ; input_type ; output_type ; body ; result } : AST.lambda = l in