From 612f8aaf5ecd4760481d84b7b89f8cad215723c1 Mon Sep 17 00:00:00 2001
From: Pierre-Emmanuel Wulfman <pierre.emmanuel.wulfman@gmail.com>
Date: Fri, 29 May 2020 16:06:44 +0200
Subject: [PATCH 1/3] vesion 1

---
 src/passes/3-self_ast_imperative/helpers.ml      | 15 +++++++++++++++
 .../4-imperative_to_sugar/imperative_to_sugar.ml | 16 +++++++++++++---
 src/passes/5-self_ast_sugar/helpers.ml           | 15 +++++++++++++++
 src/passes/6-sugar_to_core/sugar_to_core.ml      |  9 +++++++++
 src/stages/1-ast_imperative/PP.ml                |  5 +++++
 src/stages/1-ast_imperative/combinators.ml       |  1 +
 src/stages/1-ast_imperative/combinators.mli      |  1 +
 src/stages/1-ast_imperative/types.ml             |  2 ++
 src/stages/2-ast_sugar/PP.ml                     |  5 +++++
 src/stages/2-ast_sugar/combinators.ml            |  1 +
 src/stages/2-ast_sugar/combinators.mli           |  1 +
 src/stages/2-ast_sugar/types.ml                  |  2 ++
 12 files changed, 70 insertions(+), 3 deletions(-)

diff --git a/src/passes/3-self_ast_imperative/helpers.ml b/src/passes/3-self_ast_imperative/helpers.ml
index e08e1ef53..66e0ef7d2 100644
--- a/src/passes/3-self_ast_imperative/helpers.ml
+++ b/src/passes/3-self_ast_imperative/helpers.ml
@@ -82,6 +82,11 @@ let rec fold_expression : 'a folder -> 'a -> expression -> 'a result = fun f ini
      let%bind res = self init' tuple in
      ok res
     )
+  | E_tuple_destruct {tuple; next} -> (
+    let%bind res = self init' tuple in
+    let%bind res = self res next in
+    ok res
+  )
   | E_let_in { let_binder = _ ; rhs ; let_result } -> (
       let%bind res = self init' rhs in
       let%bind res = self res let_result in
@@ -205,6 +210,11 @@ let rec map_expression : exp_mapper -> expression -> expression result = fun f e
      let%bind tuple = self tuple in
      return @@ E_tuple_accessor {tuple;path}
     )
+  | E_tuple_destruct {tuple;fields;next} -> (
+     let%bind tuple = self tuple in
+     let%bind next  = self next in
+     return @@ E_tuple_destruct {tuple;fields;next}
+    )
   | E_constructor c -> (
       let%bind e' = self c.element in
       return @@ E_constructor {c with element = e'}
@@ -384,6 +394,11 @@ let rec fold_map_expression : 'a fold_mapper -> 'a -> expression -> ('a * expres
      let%bind (res, tuple) = self init' tuple in
      ok (res, return @@ E_tuple_accessor {tuple; path})
     )
+  | E_tuple_destruct {tuple;fields;next} -> (
+     let%bind (res,tuple) = self init' tuple in
+     let%bind (res,next)  = self res next in
+     ok (res, return @@ E_tuple_destruct {tuple;fields;next})
+     )
   | E_constructor c -> (
       let%bind (res,e') = self init' c.element in
       ok (res, return @@ E_constructor {c with element = e'})
diff --git a/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml b/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml
index 224c2de10..6ee20e2cd 100644
--- a/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml
+++ b/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml
@@ -57,9 +57,10 @@ let repair_mutable_variable_in_matching (match_body : O.expression) (element_nam
       | E_constant _
       | E_skip
       | E_literal _ | E_variable _
-      | E_application _ | E_lambda _| E_recursive _
-      | E_constructor _ | E_record _| E_record_accessor _|E_record_update _
-      | E_ascription _  | E_sequence _ | E_tuple _ | E_tuple_accessor _ | E_tuple_update _
+      | E_application _ | E_lambda _| E_recursive _ | E_constructor _ 
+      | E_record _| E_record_accessor _|E_record_update _ | E_ascription _  
+      | E_sequence _ | E_tuple _ | E_tuple_accessor _ | E_tuple_update _
+      | E_tuple_destruct _
       | E_map _ | E_big_map _ |E_list _ | E_set _ |E_look_up _
        -> ok (true, (decl_var, free_var),ass_exp)
     )
@@ -104,6 +105,7 @@ and repair_mutable_variable_in_loops (for_body : O.expression) (element_names :
       | E_application _ | E_lambda _| E_recursive _
       | E_constructor _ | E_record _| E_record_accessor _|E_record_update _
       | E_ascription _  | E_sequence _ | E_tuple _ | E_tuple_accessor _ | E_tuple_update _
+      | E_tuple_destruct _
       | E_map _ | E_big_map _ |E_list _ | E_set _ |E_look_up _
        -> ok (true, (decl_var, free_var),ass_exp)
     )
@@ -335,6 +337,10 @@ and compile_expression' : I.expression -> (O.expression option -> O.expression)
       let%bind tuple = compile_expression tuple in
       let%bind update = compile_expression update in
       return @@ O.e_tuple_update ~loc tuple path update
+    | I.E_tuple_destruct {tuple; fields; next} ->
+      let%bind tuple = compile_expression tuple in
+      let%bind next  = compile_expression next in
+      return @@ O.e_tuple_destruct ~loc tuple fields next
     | I.E_assign {variable; access_path; expression} ->
       let accessor ?loc s a =
         match a with 
@@ -724,6 +730,10 @@ let rec uncompile_expression' : O.expression -> I.expression result =
     let%bind tuple  = uncompile_expression' tuple in
     let%bind update = uncompile_expression' update in
     return @@ I.E_tuple_update {tuple;path;update}
+  | O.E_tuple_destruct {tuple; fields; next} ->
+    let%bind tuple = uncompile_expression' tuple in
+    let%bind next  = uncompile_expression' next in
+    return @@ I.E_tuple_destruct {tuple; fields; next}
   | O.E_map map ->
     let%bind map = bind_map_list (
       bind_map_pair uncompile_expression'
diff --git a/src/passes/5-self_ast_sugar/helpers.ml b/src/passes/5-self_ast_sugar/helpers.ml
index 953a8910f..2149ea9f8 100644
--- a/src/passes/5-self_ast_sugar/helpers.ml
+++ b/src/passes/5-self_ast_sugar/helpers.ml
@@ -99,6 +99,11 @@ let rec fold_expression : 'a folder -> 'a -> expression -> 'a result = fun f ini
      let%bind res = self init' tuple in
      ok res
     )
+  | E_tuple_destruct {tuple; next} -> (
+    let%bind res = self init' tuple in
+    let%bind res = self res next in
+    ok res
+  )
      
 
 and fold_cases : 'a folder -> 'a -> matching_expr -> 'a result = fun f init m ->
@@ -225,6 +230,11 @@ let rec map_expression : exp_mapper -> expression -> expression result = fun f e
      let%bind tuple = self tuple in
      return @@ E_tuple_accessor {tuple;path}
     )
+  | E_tuple_destruct {tuple;fields;next} -> (
+     let%bind tuple = self tuple in
+     let%bind next  = self next in
+     return @@ E_tuple_destruct {tuple;fields;next}
+    )
   | E_literal _ | E_variable _ | E_skip as e' -> return e'
 
 and map_type_expression : ty_exp_mapper -> type_expression -> type_expression result = fun f te ->
@@ -353,6 +363,11 @@ let rec fold_map_expression : 'a fold_mapper -> 'a -> expression -> ('a * expres
      let%bind (res, tuple) = self init' tuple in
      ok (res, return @@ E_tuple_accessor {tuple; path})
     )
+  | E_tuple_destruct {tuple;fields;next} -> (
+     let%bind (res,tuple) = self init' tuple in
+     let%bind (res,next)  = self res next in
+     ok (res, return @@ E_tuple_destruct {tuple;fields;next})
+     )
   | E_constructor c -> (
       let%bind (res,e') = self init' c.element in
       ok (res, return @@ E_constructor {c with element = e'})
diff --git a/src/passes/6-sugar_to_core/sugar_to_core.ml b/src/passes/6-sugar_to_core/sugar_to_core.ml
index 165ff5577..22a89faa2 100644
--- a/src/passes/6-sugar_to_core/sugar_to_core.ml
+++ b/src/passes/6-sugar_to_core/sugar_to_core.ml
@@ -193,6 +193,15 @@ let rec compile_expression : I.expression -> O.expression result =
       let path        = O.Label (string_of_int path) in
       let%bind update = compile_expression update in
       return @@ O.E_record_update {record;path;update}
+    | I.E_tuple_destruct {tuple; fields; next} ->
+      let%bind record = compile_expression tuple in
+      let%bind next   = compile_expression next in
+      let aux ((index,e) : int * _ ) (field: I.expression_variable) =
+        let f = fun expr -> O.e_let_in (field, None) false (O.e_record_accessor record (string_of_int index)) expr in
+        (index+1, fun expr -> e (f expr))
+      in
+      let (_,header) = List.fold_left aux (0, fun e -> e) fields in
+      ok @@ header next
 
 and compile_lambda : I.lambda -> O.lambda result =
   fun {binder;input_type;output_type;result}->
diff --git a/src/stages/1-ast_imperative/PP.ml b/src/stages/1-ast_imperative/PP.ml
index 6a2c835db..3147e4844 100644
--- a/src/stages/1-ast_imperative/PP.ml
+++ b/src/stages/1-ast_imperative/PP.ml
@@ -136,6 +136,11 @@ and expression_content ppf (ec : expression_content) =
       fprintf ppf "%a.%d" expression ta.tuple ta.path
   | E_tuple_update {tuple; path; update} ->
       fprintf ppf "{ %a with %d = %a }" expression tuple path expression update
+  | E_tuple_destruct {tuple; fields; next} ->
+      fprintf ppf "{ let (%a) = %a in %a"
+        (list_sep_d expression_variable) fields
+        expression tuple
+        expression next
   | E_assign {variable; access_path; expression=e} ->
       fprintf ppf "%a%a := %a" 
         expression_variable variable
diff --git a/src/stages/1-ast_imperative/combinators.ml b/src/stages/1-ast_imperative/combinators.ml
index 4a4e88ed3..51a3330ae 100644
--- a/src/stages/1-ast_imperative/combinators.ml
+++ b/src/stages/1-ast_imperative/combinators.ml
@@ -140,6 +140,7 @@ let e_annotation ?loc anno_expr ty = make_e ?loc @@ E_ascription {anno_expr; typ
 let e_tuple ?loc lst : expression = make_e ?loc @@ E_tuple lst
 let e_tuple_accessor ?loc tuple path : expression = make_e ?loc @@ E_tuple_accessor {tuple; path}
 let e_tuple_update ?loc tuple path update : expression = make_e ?loc @@ E_tuple_update {tuple; path; update}
+let e_tuple_destruct ?loc tuple fields next = make_e ?loc @@ E_tuple_destruct {tuple; fields; next}
 
 let e_pair ?loc a b  : expression = e_tuple ?loc [a;b]
 let e_cond ?loc condition then_clause else_clause = make_e ?loc @@ E_cond {condition;then_clause;else_clause}
diff --git a/src/stages/1-ast_imperative/combinators.mli b/src/stages/1-ast_imperative/combinators.mli
index 46e02fa9e..8c8047179 100644
--- a/src/stages/1-ast_imperative/combinators.mli
+++ b/src/stages/1-ast_imperative/combinators.mli
@@ -105,6 +105,7 @@ val e_annotation : ?loc:Location.t -> expression -> type_expression -> expressio
 val e_tuple : ?loc:Location.t -> expression list -> expression
 val e_tuple_accessor : ?loc:Location.t -> expression -> int -> expression
 val e_tuple_update : ?loc:Location.t -> expression -> int -> expression -> expression
+val e_tuple_destruct : ?loc:Location.t -> expression -> expression_variable list -> expression -> expression
 val e_pair : ?loc:Location.t -> expression -> expression -> expression
 
 val e_cond: ?loc:Location.t -> expression -> expression -> expression -> expression
diff --git a/src/stages/1-ast_imperative/types.ml b/src/stages/1-ast_imperative/types.ml
index 4651c1f9f..1989c9e7f 100644
--- a/src/stages/1-ast_imperative/types.ml
+++ b/src/stages/1-ast_imperative/types.ml
@@ -77,6 +77,7 @@ and expression_content =
   | E_tuple of expression list
   | E_tuple_accessor of tuple_accessor
   | E_tuple_update   of tuple_update
+  | E_tuple_destruct of tuple_destruct
   (* Data Structures *)
   | E_map of (expression * expression) list 
   | E_big_map of (expression * expression) list
@@ -144,6 +145,7 @@ and sequence = {
 
 and tuple_accessor = {tuple: expression; path: int}
 and tuple_update   = {tuple: expression; path: int ; update: expression}
+and tuple_destruct = {tuple: expression; fields : expression_variable list; next : expression}
 
 and assign = {
   variable : expression_variable;
diff --git a/src/stages/2-ast_sugar/PP.ml b/src/stages/2-ast_sugar/PP.ml
index 3f348c52c..394115870 100644
--- a/src/stages/2-ast_sugar/PP.ml
+++ b/src/stages/2-ast_sugar/PP.ml
@@ -129,6 +129,11 @@ and expression_content ppf (ec : expression_content) =
       fprintf ppf "%a.%d" expression ta.tuple ta.path
   | E_tuple_update {tuple; path; update} ->
       fprintf ppf "{ %a with %d = %a }" expression tuple path expression update
+  | E_tuple_destruct {tuple; fields; next} ->
+      fprintf ppf "{ let (%a) = %a in %a"
+        (list_sep_d expression_variable) fields
+        expression tuple
+        expression next
 
 and option_type_name ppf
     ((n, ty_opt) : expression_variable * type_expression option) =
diff --git a/src/stages/2-ast_sugar/combinators.ml b/src/stages/2-ast_sugar/combinators.ml
index 8c8890748..8d45a624d 100644
--- a/src/stages/2-ast_sugar/combinators.ml
+++ b/src/stages/2-ast_sugar/combinators.ml
@@ -129,6 +129,7 @@ let e_annotation ?loc anno_expr ty = make_e ?loc @@ E_ascription {anno_expr; typ
 let e_tuple ?loc lst : expression = make_e ?loc @@ E_tuple lst
 let e_tuple_accessor ?loc tuple path = make_e ?loc @@ E_tuple_accessor {tuple; path}
 let e_tuple_update ?loc tuple path update = make_e ?loc @@ E_tuple_update {tuple; path; update}
+let e_tuple_destruct ?loc tuple fields next = make_e ?loc @@ E_tuple_destruct {tuple; fields; next}
 let e_pair ?loc a b  : expression = e_tuple ?loc [a;b]
 
 let e_cond ?loc condition then_clause else_clause = make_e ?loc @@ E_cond {condition;then_clause;else_clause}
diff --git a/src/stages/2-ast_sugar/combinators.mli b/src/stages/2-ast_sugar/combinators.mli
index 3faebef21..bdf8b2b5e 100644
--- a/src/stages/2-ast_sugar/combinators.mli
+++ b/src/stages/2-ast_sugar/combinators.mli
@@ -85,6 +85,7 @@ val e_annotation : ?loc:Location.t -> expression -> type_expression -> expressio
 val e_tuple : ?loc:Location.t -> expression list -> expression
 val e_tuple_accessor : ?loc:Location.t -> expression -> int -> expression
 val e_tuple_update : ?loc:Location.t -> expression -> int -> expression -> expression
+val e_tuple_destruct : ?loc:Location.t -> expression -> expression_variable list -> expression -> expression
 val e_pair : ?loc:Location.t -> expression -> expression -> expression
 
 val e_cond: ?loc:Location.t -> expression -> expression -> expression -> expression
diff --git a/src/stages/2-ast_sugar/types.ml b/src/stages/2-ast_sugar/types.ml
index 88df116fb..a24c4ebde 100644
--- a/src/stages/2-ast_sugar/types.ml
+++ b/src/stages/2-ast_sugar/types.ml
@@ -77,6 +77,7 @@ and expression_content =
   | E_tuple of expression list
   | E_tuple_accessor of tuple_accessor
   | E_tuple_update   of tuple_update
+  | E_tuple_destruct of tuple_destruct
   (* Data Structures *)
   | E_map of (expression * expression) list 
   | E_big_map of (expression * expression) list
@@ -138,6 +139,7 @@ and sequence = {
 
 and tuple_accessor = {tuple: expression; path: int}
 and tuple_update   = {tuple: expression; path: int ; update: expression}
+and tuple_destruct = {tuple: expression; fields : expression_variable list; next : expression}
 
 and environment_element_definition =
   | ED_binder

From d6448727290fb0192fbef50a5bf99e4df59ad45c Mon Sep 17 00:00:00 2001
From: Pierre-Emmanuel Wulfman <pierre.emmanuel.wulfman@gmail.com>
Date: Fri, 29 May 2020 17:49:37 +0200
Subject: [PATCH 2/3] version 2

---
 src/passes/3-self_ast_imperative/helpers.ml      |  8 ++++----
 .../4-imperative_to_sugar/imperative_to_sugar.ml | 10 ++++++----
 src/passes/5-self_ast_sugar/helpers.ml           |  8 ++++----
 src/passes/6-sugar_to_core/sugar_to_core.ml      | 16 ++++++++++++----
 src/stages/1-ast_imperative/PP.ml                |  2 +-
 src/stages/1-ast_imperative/combinators.ml       |  2 +-
 src/stages/1-ast_imperative/combinators.mli      |  2 +-
 src/stages/1-ast_imperative/types.ml             |  2 +-
 src/stages/2-ast_sugar/PP.ml                     |  2 +-
 src/stages/2-ast_sugar/combinators.ml            |  2 +-
 src/stages/2-ast_sugar/combinators.mli           |  2 +-
 src/stages/2-ast_sugar/types.ml                  |  2 +-
 12 files changed, 34 insertions(+), 24 deletions(-)

diff --git a/src/passes/3-self_ast_imperative/helpers.ml b/src/passes/3-self_ast_imperative/helpers.ml
index 66e0ef7d2..79e3b91c5 100644
--- a/src/passes/3-self_ast_imperative/helpers.ml
+++ b/src/passes/3-self_ast_imperative/helpers.ml
@@ -210,10 +210,10 @@ let rec map_expression : exp_mapper -> expression -> expression result = fun f e
      let%bind tuple = self tuple in
      return @@ E_tuple_accessor {tuple;path}
     )
-  | E_tuple_destruct {tuple;fields;next} -> (
+  | E_tuple_destruct {tuple;fields;field_types;next} -> (
      let%bind tuple = self tuple in
      let%bind next  = self next in
-     return @@ E_tuple_destruct {tuple;fields;next}
+     return @@ E_tuple_destruct {tuple;fields;field_types;next}
     )
   | E_constructor c -> (
       let%bind e' = self c.element in
@@ -394,10 +394,10 @@ let rec fold_map_expression : 'a fold_mapper -> 'a -> expression -> ('a * expres
      let%bind (res, tuple) = self init' tuple in
      ok (res, return @@ E_tuple_accessor {tuple; path})
     )
-  | E_tuple_destruct {tuple;fields;next} -> (
+  | E_tuple_destruct {tuple;fields;field_types;next} -> (
      let%bind (res,tuple) = self init' tuple in
      let%bind (res,next)  = self res next in
-     ok (res, return @@ E_tuple_destruct {tuple;fields;next})
+     ok (res, return @@ E_tuple_destruct {tuple;fields;field_types;next})
      )
   | E_constructor c -> (
       let%bind (res,e') = self init' c.element in
diff --git a/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml b/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml
index 6ee20e2cd..fda433669 100644
--- a/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml
+++ b/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml
@@ -337,10 +337,11 @@ and compile_expression' : I.expression -> (O.expression option -> O.expression)
       let%bind tuple = compile_expression tuple in
       let%bind update = compile_expression update in
       return @@ O.e_tuple_update ~loc tuple path update
-    | I.E_tuple_destruct {tuple; fields; next} ->
+    | I.E_tuple_destruct {tuple; fields; field_types; next} ->
       let%bind tuple = compile_expression tuple in
       let%bind next  = compile_expression next in
-      return @@ O.e_tuple_destruct ~loc tuple fields next
+      let%bind field_types = bind_map_option (bind_map_list compile_type_expression) field_types in
+      return @@ O.e_tuple_destruct ~loc tuple fields field_types next
     | I.E_assign {variable; access_path; expression} ->
       let accessor ?loc s a =
         match a with 
@@ -730,10 +731,11 @@ let rec uncompile_expression' : O.expression -> I.expression result =
     let%bind tuple  = uncompile_expression' tuple in
     let%bind update = uncompile_expression' update in
     return @@ I.E_tuple_update {tuple;path;update}
-  | O.E_tuple_destruct {tuple; fields; next} ->
+  | O.E_tuple_destruct {tuple; fields; field_types; next} ->
     let%bind tuple = uncompile_expression' tuple in
     let%bind next  = uncompile_expression' next in
-    return @@ I.E_tuple_destruct {tuple; fields; next}
+    let%bind field_types = bind_map_option (bind_map_list uncompile_type_expression) field_types in
+    return @@ I.E_tuple_destruct {tuple; fields; field_types; next}
   | O.E_map map ->
     let%bind map = bind_map_list (
       bind_map_pair uncompile_expression'
diff --git a/src/passes/5-self_ast_sugar/helpers.ml b/src/passes/5-self_ast_sugar/helpers.ml
index 2149ea9f8..95d35d356 100644
--- a/src/passes/5-self_ast_sugar/helpers.ml
+++ b/src/passes/5-self_ast_sugar/helpers.ml
@@ -230,10 +230,10 @@ let rec map_expression : exp_mapper -> expression -> expression result = fun f e
      let%bind tuple = self tuple in
      return @@ E_tuple_accessor {tuple;path}
     )
-  | E_tuple_destruct {tuple;fields;next} -> (
+  | E_tuple_destruct {tuple;fields;field_types;next} -> (
      let%bind tuple = self tuple in
      let%bind next  = self next in
-     return @@ E_tuple_destruct {tuple;fields;next}
+     return @@ E_tuple_destruct {tuple;fields;field_types;next}
     )
   | E_literal _ | E_variable _ | E_skip as e' -> return e'
 
@@ -363,10 +363,10 @@ let rec fold_map_expression : 'a fold_mapper -> 'a -> expression -> ('a * expres
      let%bind (res, tuple) = self init' tuple in
      ok (res, return @@ E_tuple_accessor {tuple; path})
     )
-  | E_tuple_destruct {tuple;fields;next} -> (
+  | E_tuple_destruct {tuple;fields;field_types;next} -> (
      let%bind (res,tuple) = self init' tuple in
      let%bind (res,next)  = self res next in
-     ok (res, return @@ E_tuple_destruct {tuple;fields;next})
+     ok (res, return @@ E_tuple_destruct {tuple;fields;field_types;next})
      )
   | E_constructor c -> (
       let%bind (res,e') = self init' c.element in
diff --git a/src/passes/6-sugar_to_core/sugar_to_core.ml b/src/passes/6-sugar_to_core/sugar_to_core.ml
index 22a89faa2..05d2600da 100644
--- a/src/passes/6-sugar_to_core/sugar_to_core.ml
+++ b/src/passes/6-sugar_to_core/sugar_to_core.ml
@@ -193,14 +193,22 @@ let rec compile_expression : I.expression -> O.expression result =
       let path        = O.Label (string_of_int path) in
       let%bind update = compile_expression update in
       return @@ O.E_record_update {record;path;update}
-    | I.E_tuple_destruct {tuple; fields; next} ->
+    | I.E_tuple_destruct {tuple; fields; field_types; next} ->
+      let combine fields field_types =
+        match field_types with
+          Some ft -> List.combine fields @@ List.map (fun x -> Some x) ft
+        | None    -> List.map (fun x -> (x, None)) fields
+      in
       let%bind record = compile_expression tuple in
       let%bind next   = compile_expression next in
-      let aux ((index,e) : int * _ ) (field: I.expression_variable) =
-        let f = fun expr -> O.e_let_in (field, None) false (O.e_record_accessor record (string_of_int index)) expr in
+      let%bind field_types = bind_map_option (bind_map_list idle_type_expression) field_types in
+      let aux ((index,e) : int * _ ) (field: O.expression_variable * O.type_expression option) =
+        let f = fun expr -> O.e_let_in field false (O.e_record_accessor record (string_of_int index)) expr in
         (index+1, fun expr -> e (f expr))
       in
-      let (_,header) = List.fold_left aux (0, fun e -> e) fields in
+      let (_,header) = List.fold_left aux (0, fun e -> e) @@
+        combine fields field_types
+      in
       ok @@ header next
 
 and compile_lambda : I.lambda -> O.lambda result =
diff --git a/src/stages/1-ast_imperative/PP.ml b/src/stages/1-ast_imperative/PP.ml
index 3147e4844..081e5743a 100644
--- a/src/stages/1-ast_imperative/PP.ml
+++ b/src/stages/1-ast_imperative/PP.ml
@@ -136,7 +136,7 @@ and expression_content ppf (ec : expression_content) =
       fprintf ppf "%a.%d" expression ta.tuple ta.path
   | E_tuple_update {tuple; path; update} ->
       fprintf ppf "{ %a with %d = %a }" expression tuple path expression update
-  | E_tuple_destruct {tuple; fields; next} ->
+  | E_tuple_destruct {tuple; fields; next; _} ->
       fprintf ppf "{ let (%a) = %a in %a"
         (list_sep_d expression_variable) fields
         expression tuple
diff --git a/src/stages/1-ast_imperative/combinators.ml b/src/stages/1-ast_imperative/combinators.ml
index 51a3330ae..586c36c07 100644
--- a/src/stages/1-ast_imperative/combinators.ml
+++ b/src/stages/1-ast_imperative/combinators.ml
@@ -140,7 +140,7 @@ let e_annotation ?loc anno_expr ty = make_e ?loc @@ E_ascription {anno_expr; typ
 let e_tuple ?loc lst : expression = make_e ?loc @@ E_tuple lst
 let e_tuple_accessor ?loc tuple path : expression = make_e ?loc @@ E_tuple_accessor {tuple; path}
 let e_tuple_update ?loc tuple path update : expression = make_e ?loc @@ E_tuple_update {tuple; path; update}
-let e_tuple_destruct ?loc tuple fields next = make_e ?loc @@ E_tuple_destruct {tuple; fields; next}
+let e_tuple_destruct ?loc tuple fields field_types next = make_e ?loc @@ E_tuple_destruct {tuple; fields; field_types; next}
 
 let e_pair ?loc a b  : expression = e_tuple ?loc [a;b]
 let e_cond ?loc condition then_clause else_clause = make_e ?loc @@ E_cond {condition;then_clause;else_clause}
diff --git a/src/stages/1-ast_imperative/combinators.mli b/src/stages/1-ast_imperative/combinators.mli
index 8c8047179..68272942c 100644
--- a/src/stages/1-ast_imperative/combinators.mli
+++ b/src/stages/1-ast_imperative/combinators.mli
@@ -105,7 +105,7 @@ val e_annotation : ?loc:Location.t -> expression -> type_expression -> expressio
 val e_tuple : ?loc:Location.t -> expression list -> expression
 val e_tuple_accessor : ?loc:Location.t -> expression -> int -> expression
 val e_tuple_update : ?loc:Location.t -> expression -> int -> expression -> expression
-val e_tuple_destruct : ?loc:Location.t -> expression -> expression_variable list -> expression -> expression
+val e_tuple_destruct : ?loc:Location.t -> expression -> expression_variable list -> type_expression list option -> expression -> expression
 val e_pair : ?loc:Location.t -> expression -> expression -> expression
 
 val e_cond: ?loc:Location.t -> expression -> expression -> expression -> expression
diff --git a/src/stages/1-ast_imperative/types.ml b/src/stages/1-ast_imperative/types.ml
index 1989c9e7f..19ab16d58 100644
--- a/src/stages/1-ast_imperative/types.ml
+++ b/src/stages/1-ast_imperative/types.ml
@@ -145,7 +145,7 @@ and sequence = {
 
 and tuple_accessor = {tuple: expression; path: int}
 and tuple_update   = {tuple: expression; path: int ; update: expression}
-and tuple_destruct = {tuple: expression; fields : expression_variable list; next : expression}
+and tuple_destruct = {tuple: expression; fields : expression_variable list; field_types : type_expression list option; next : expression}
 
 and assign = {
   variable : expression_variable;
diff --git a/src/stages/2-ast_sugar/PP.ml b/src/stages/2-ast_sugar/PP.ml
index 394115870..31b991f07 100644
--- a/src/stages/2-ast_sugar/PP.ml
+++ b/src/stages/2-ast_sugar/PP.ml
@@ -129,7 +129,7 @@ and expression_content ppf (ec : expression_content) =
       fprintf ppf "%a.%d" expression ta.tuple ta.path
   | E_tuple_update {tuple; path; update} ->
       fprintf ppf "{ %a with %d = %a }" expression tuple path expression update
-  | E_tuple_destruct {tuple; fields; next} ->
+  | E_tuple_destruct {tuple; fields; next; _} ->
       fprintf ppf "{ let (%a) = %a in %a"
         (list_sep_d expression_variable) fields
         expression tuple
diff --git a/src/stages/2-ast_sugar/combinators.ml b/src/stages/2-ast_sugar/combinators.ml
index 8d45a624d..dcf8ed421 100644
--- a/src/stages/2-ast_sugar/combinators.ml
+++ b/src/stages/2-ast_sugar/combinators.ml
@@ -129,7 +129,7 @@ let e_annotation ?loc anno_expr ty = make_e ?loc @@ E_ascription {anno_expr; typ
 let e_tuple ?loc lst : expression = make_e ?loc @@ E_tuple lst
 let e_tuple_accessor ?loc tuple path = make_e ?loc @@ E_tuple_accessor {tuple; path}
 let e_tuple_update ?loc tuple path update = make_e ?loc @@ E_tuple_update {tuple; path; update}
-let e_tuple_destruct ?loc tuple fields next = make_e ?loc @@ E_tuple_destruct {tuple; fields; next}
+let e_tuple_destruct ?loc tuple fields field_types next = make_e ?loc @@ E_tuple_destruct {tuple; fields; field_types; next}
 let e_pair ?loc a b  : expression = e_tuple ?loc [a;b]
 
 let e_cond ?loc condition then_clause else_clause = make_e ?loc @@ E_cond {condition;then_clause;else_clause}
diff --git a/src/stages/2-ast_sugar/combinators.mli b/src/stages/2-ast_sugar/combinators.mli
index bdf8b2b5e..94529b898 100644
--- a/src/stages/2-ast_sugar/combinators.mli
+++ b/src/stages/2-ast_sugar/combinators.mli
@@ -85,7 +85,7 @@ val e_annotation : ?loc:Location.t -> expression -> type_expression -> expressio
 val e_tuple : ?loc:Location.t -> expression list -> expression
 val e_tuple_accessor : ?loc:Location.t -> expression -> int -> expression
 val e_tuple_update : ?loc:Location.t -> expression -> int -> expression -> expression
-val e_tuple_destruct : ?loc:Location.t -> expression -> expression_variable list -> expression -> expression
+val e_tuple_destruct : ?loc:Location.t -> expression -> expression_variable list -> type_expression list option -> expression -> expression
 val e_pair : ?loc:Location.t -> expression -> expression -> expression
 
 val e_cond: ?loc:Location.t -> expression -> expression -> expression -> expression
diff --git a/src/stages/2-ast_sugar/types.ml b/src/stages/2-ast_sugar/types.ml
index a24c4ebde..8c3422de6 100644
--- a/src/stages/2-ast_sugar/types.ml
+++ b/src/stages/2-ast_sugar/types.ml
@@ -139,7 +139,7 @@ and sequence = {
 
 and tuple_accessor = {tuple: expression; path: int}
 and tuple_update   = {tuple: expression; path: int ; update: expression}
-and tuple_destruct = {tuple: expression; fields : expression_variable list; next : expression}
+and tuple_destruct = {tuple: expression; fields : expression_variable list; field_types : type_expression list option; next : expression}
 
 and environment_element_definition =
   | ED_binder

From 2d43f678931a7199ef368441ab940f587debe89d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Suzanne=20Dup=C3=A9ron?= <georges.duperon@nomadic-labs.com>
Date: Sun, 31 May 2020 17:25:40 +0000
Subject: [PATCH 3/3] Revert "Merge branch 'ast/tuple_destruct' into 'dev'"

This reverts merge request !650
---
 src/passes/3-self_ast_imperative/helpers.ml    | 15 ---------------
 .../imperative_to_sugar.ml                     | 18 +++---------------
 src/passes/5-self_ast_sugar/helpers.ml         | 15 ---------------
 src/passes/6-sugar_to_core/sugar_to_core.ml    | 17 -----------------
 src/stages/1-ast_imperative/PP.ml              |  5 -----
 src/stages/1-ast_imperative/combinators.ml     |  1 -
 src/stages/1-ast_imperative/combinators.mli    |  1 -
 src/stages/1-ast_imperative/types.ml           |  2 --
 src/stages/2-ast_sugar/PP.ml                   |  5 -----
 src/stages/2-ast_sugar/combinators.ml          |  1 -
 src/stages/2-ast_sugar/combinators.mli         |  1 -
 src/stages/2-ast_sugar/types.ml                |  2 --
 12 files changed, 3 insertions(+), 80 deletions(-)

diff --git a/src/passes/3-self_ast_imperative/helpers.ml b/src/passes/3-self_ast_imperative/helpers.ml
index 79e3b91c5..e08e1ef53 100644
--- a/src/passes/3-self_ast_imperative/helpers.ml
+++ b/src/passes/3-self_ast_imperative/helpers.ml
@@ -82,11 +82,6 @@ let rec fold_expression : 'a folder -> 'a -> expression -> 'a result = fun f ini
      let%bind res = self init' tuple in
      ok res
     )
-  | E_tuple_destruct {tuple; next} -> (
-    let%bind res = self init' tuple in
-    let%bind res = self res next in
-    ok res
-  )
   | E_let_in { let_binder = _ ; rhs ; let_result } -> (
       let%bind res = self init' rhs in
       let%bind res = self res let_result in
@@ -210,11 +205,6 @@ let rec map_expression : exp_mapper -> expression -> expression result = fun f e
      let%bind tuple = self tuple in
      return @@ E_tuple_accessor {tuple;path}
     )
-  | E_tuple_destruct {tuple;fields;field_types;next} -> (
-     let%bind tuple = self tuple in
-     let%bind next  = self next in
-     return @@ E_tuple_destruct {tuple;fields;field_types;next}
-    )
   | E_constructor c -> (
       let%bind e' = self c.element in
       return @@ E_constructor {c with element = e'}
@@ -394,11 +384,6 @@ let rec fold_map_expression : 'a fold_mapper -> 'a -> expression -> ('a * expres
      let%bind (res, tuple) = self init' tuple in
      ok (res, return @@ E_tuple_accessor {tuple; path})
     )
-  | E_tuple_destruct {tuple;fields;field_types;next} -> (
-     let%bind (res,tuple) = self init' tuple in
-     let%bind (res,next)  = self res next in
-     ok (res, return @@ E_tuple_destruct {tuple;fields;field_types;next})
-     )
   | E_constructor c -> (
       let%bind (res,e') = self init' c.element in
       ok (res, return @@ E_constructor {c with element = e'})
diff --git a/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml b/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml
index fda433669..224c2de10 100644
--- a/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml
+++ b/src/passes/4-imperative_to_sugar/imperative_to_sugar.ml
@@ -57,10 +57,9 @@ let repair_mutable_variable_in_matching (match_body : O.expression) (element_nam
       | E_constant _
       | E_skip
       | E_literal _ | E_variable _
-      | E_application _ | E_lambda _| E_recursive _ | E_constructor _ 
-      | E_record _| E_record_accessor _|E_record_update _ | E_ascription _  
-      | E_sequence _ | E_tuple _ | E_tuple_accessor _ | E_tuple_update _
-      | E_tuple_destruct _
+      | E_application _ | E_lambda _| E_recursive _
+      | E_constructor _ | E_record _| E_record_accessor _|E_record_update _
+      | E_ascription _  | E_sequence _ | E_tuple _ | E_tuple_accessor _ | E_tuple_update _
       | E_map _ | E_big_map _ |E_list _ | E_set _ |E_look_up _
        -> ok (true, (decl_var, free_var),ass_exp)
     )
@@ -105,7 +104,6 @@ and repair_mutable_variable_in_loops (for_body : O.expression) (element_names :
       | E_application _ | E_lambda _| E_recursive _
       | E_constructor _ | E_record _| E_record_accessor _|E_record_update _
       | E_ascription _  | E_sequence _ | E_tuple _ | E_tuple_accessor _ | E_tuple_update _
-      | E_tuple_destruct _
       | E_map _ | E_big_map _ |E_list _ | E_set _ |E_look_up _
        -> ok (true, (decl_var, free_var),ass_exp)
     )
@@ -337,11 +335,6 @@ and compile_expression' : I.expression -> (O.expression option -> O.expression)
       let%bind tuple = compile_expression tuple in
       let%bind update = compile_expression update in
       return @@ O.e_tuple_update ~loc tuple path update
-    | I.E_tuple_destruct {tuple; fields; field_types; next} ->
-      let%bind tuple = compile_expression tuple in
-      let%bind next  = compile_expression next in
-      let%bind field_types = bind_map_option (bind_map_list compile_type_expression) field_types in
-      return @@ O.e_tuple_destruct ~loc tuple fields field_types next
     | I.E_assign {variable; access_path; expression} ->
       let accessor ?loc s a =
         match a with 
@@ -731,11 +724,6 @@ let rec uncompile_expression' : O.expression -> I.expression result =
     let%bind tuple  = uncompile_expression' tuple in
     let%bind update = uncompile_expression' update in
     return @@ I.E_tuple_update {tuple;path;update}
-  | O.E_tuple_destruct {tuple; fields; field_types; next} ->
-    let%bind tuple = uncompile_expression' tuple in
-    let%bind next  = uncompile_expression' next in
-    let%bind field_types = bind_map_option (bind_map_list uncompile_type_expression) field_types in
-    return @@ I.E_tuple_destruct {tuple; fields; field_types; next}
   | O.E_map map ->
     let%bind map = bind_map_list (
       bind_map_pair uncompile_expression'
diff --git a/src/passes/5-self_ast_sugar/helpers.ml b/src/passes/5-self_ast_sugar/helpers.ml
index 95d35d356..953a8910f 100644
--- a/src/passes/5-self_ast_sugar/helpers.ml
+++ b/src/passes/5-self_ast_sugar/helpers.ml
@@ -99,11 +99,6 @@ let rec fold_expression : 'a folder -> 'a -> expression -> 'a result = fun f ini
      let%bind res = self init' tuple in
      ok res
     )
-  | E_tuple_destruct {tuple; next} -> (
-    let%bind res = self init' tuple in
-    let%bind res = self res next in
-    ok res
-  )
      
 
 and fold_cases : 'a folder -> 'a -> matching_expr -> 'a result = fun f init m ->
@@ -230,11 +225,6 @@ let rec map_expression : exp_mapper -> expression -> expression result = fun f e
      let%bind tuple = self tuple in
      return @@ E_tuple_accessor {tuple;path}
     )
-  | E_tuple_destruct {tuple;fields;field_types;next} -> (
-     let%bind tuple = self tuple in
-     let%bind next  = self next in
-     return @@ E_tuple_destruct {tuple;fields;field_types;next}
-    )
   | E_literal _ | E_variable _ | E_skip as e' -> return e'
 
 and map_type_expression : ty_exp_mapper -> type_expression -> type_expression result = fun f te ->
@@ -363,11 +353,6 @@ let rec fold_map_expression : 'a fold_mapper -> 'a -> expression -> ('a * expres
      let%bind (res, tuple) = self init' tuple in
      ok (res, return @@ E_tuple_accessor {tuple; path})
     )
-  | E_tuple_destruct {tuple;fields;field_types;next} -> (
-     let%bind (res,tuple) = self init' tuple in
-     let%bind (res,next)  = self res next in
-     ok (res, return @@ E_tuple_destruct {tuple;fields;field_types;next})
-     )
   | E_constructor c -> (
       let%bind (res,e') = self init' c.element in
       ok (res, return @@ E_constructor {c with element = e'})
diff --git a/src/passes/6-sugar_to_core/sugar_to_core.ml b/src/passes/6-sugar_to_core/sugar_to_core.ml
index 05d2600da..165ff5577 100644
--- a/src/passes/6-sugar_to_core/sugar_to_core.ml
+++ b/src/passes/6-sugar_to_core/sugar_to_core.ml
@@ -193,23 +193,6 @@ let rec compile_expression : I.expression -> O.expression result =
       let path        = O.Label (string_of_int path) in
       let%bind update = compile_expression update in
       return @@ O.E_record_update {record;path;update}
-    | I.E_tuple_destruct {tuple; fields; field_types; next} ->
-      let combine fields field_types =
-        match field_types with
-          Some ft -> List.combine fields @@ List.map (fun x -> Some x) ft
-        | None    -> List.map (fun x -> (x, None)) fields
-      in
-      let%bind record = compile_expression tuple in
-      let%bind next   = compile_expression next in
-      let%bind field_types = bind_map_option (bind_map_list idle_type_expression) field_types in
-      let aux ((index,e) : int * _ ) (field: O.expression_variable * O.type_expression option) =
-        let f = fun expr -> O.e_let_in field false (O.e_record_accessor record (string_of_int index)) expr in
-        (index+1, fun expr -> e (f expr))
-      in
-      let (_,header) = List.fold_left aux (0, fun e -> e) @@
-        combine fields field_types
-      in
-      ok @@ header next
 
 and compile_lambda : I.lambda -> O.lambda result =
   fun {binder;input_type;output_type;result}->
diff --git a/src/stages/1-ast_imperative/PP.ml b/src/stages/1-ast_imperative/PP.ml
index 081e5743a..6a2c835db 100644
--- a/src/stages/1-ast_imperative/PP.ml
+++ b/src/stages/1-ast_imperative/PP.ml
@@ -136,11 +136,6 @@ and expression_content ppf (ec : expression_content) =
       fprintf ppf "%a.%d" expression ta.tuple ta.path
   | E_tuple_update {tuple; path; update} ->
       fprintf ppf "{ %a with %d = %a }" expression tuple path expression update
-  | E_tuple_destruct {tuple; fields; next; _} ->
-      fprintf ppf "{ let (%a) = %a in %a"
-        (list_sep_d expression_variable) fields
-        expression tuple
-        expression next
   | E_assign {variable; access_path; expression=e} ->
       fprintf ppf "%a%a := %a" 
         expression_variable variable
diff --git a/src/stages/1-ast_imperative/combinators.ml b/src/stages/1-ast_imperative/combinators.ml
index 586c36c07..4a4e88ed3 100644
--- a/src/stages/1-ast_imperative/combinators.ml
+++ b/src/stages/1-ast_imperative/combinators.ml
@@ -140,7 +140,6 @@ let e_annotation ?loc anno_expr ty = make_e ?loc @@ E_ascription {anno_expr; typ
 let e_tuple ?loc lst : expression = make_e ?loc @@ E_tuple lst
 let e_tuple_accessor ?loc tuple path : expression = make_e ?loc @@ E_tuple_accessor {tuple; path}
 let e_tuple_update ?loc tuple path update : expression = make_e ?loc @@ E_tuple_update {tuple; path; update}
-let e_tuple_destruct ?loc tuple fields field_types next = make_e ?loc @@ E_tuple_destruct {tuple; fields; field_types; next}
 
 let e_pair ?loc a b  : expression = e_tuple ?loc [a;b]
 let e_cond ?loc condition then_clause else_clause = make_e ?loc @@ E_cond {condition;then_clause;else_clause}
diff --git a/src/stages/1-ast_imperative/combinators.mli b/src/stages/1-ast_imperative/combinators.mli
index 68272942c..46e02fa9e 100644
--- a/src/stages/1-ast_imperative/combinators.mli
+++ b/src/stages/1-ast_imperative/combinators.mli
@@ -105,7 +105,6 @@ val e_annotation : ?loc:Location.t -> expression -> type_expression -> expressio
 val e_tuple : ?loc:Location.t -> expression list -> expression
 val e_tuple_accessor : ?loc:Location.t -> expression -> int -> expression
 val e_tuple_update : ?loc:Location.t -> expression -> int -> expression -> expression
-val e_tuple_destruct : ?loc:Location.t -> expression -> expression_variable list -> type_expression list option -> expression -> expression
 val e_pair : ?loc:Location.t -> expression -> expression -> expression
 
 val e_cond: ?loc:Location.t -> expression -> expression -> expression -> expression
diff --git a/src/stages/1-ast_imperative/types.ml b/src/stages/1-ast_imperative/types.ml
index 19ab16d58..4651c1f9f 100644
--- a/src/stages/1-ast_imperative/types.ml
+++ b/src/stages/1-ast_imperative/types.ml
@@ -77,7 +77,6 @@ and expression_content =
   | E_tuple of expression list
   | E_tuple_accessor of tuple_accessor
   | E_tuple_update   of tuple_update
-  | E_tuple_destruct of tuple_destruct
   (* Data Structures *)
   | E_map of (expression * expression) list 
   | E_big_map of (expression * expression) list
@@ -145,7 +144,6 @@ and sequence = {
 
 and tuple_accessor = {tuple: expression; path: int}
 and tuple_update   = {tuple: expression; path: int ; update: expression}
-and tuple_destruct = {tuple: expression; fields : expression_variable list; field_types : type_expression list option; next : expression}
 
 and assign = {
   variable : expression_variable;
diff --git a/src/stages/2-ast_sugar/PP.ml b/src/stages/2-ast_sugar/PP.ml
index 31b991f07..3f348c52c 100644
--- a/src/stages/2-ast_sugar/PP.ml
+++ b/src/stages/2-ast_sugar/PP.ml
@@ -129,11 +129,6 @@ and expression_content ppf (ec : expression_content) =
       fprintf ppf "%a.%d" expression ta.tuple ta.path
   | E_tuple_update {tuple; path; update} ->
       fprintf ppf "{ %a with %d = %a }" expression tuple path expression update
-  | E_tuple_destruct {tuple; fields; next; _} ->
-      fprintf ppf "{ let (%a) = %a in %a"
-        (list_sep_d expression_variable) fields
-        expression tuple
-        expression next
 
 and option_type_name ppf
     ((n, ty_opt) : expression_variable * type_expression option) =
diff --git a/src/stages/2-ast_sugar/combinators.ml b/src/stages/2-ast_sugar/combinators.ml
index dcf8ed421..8c8890748 100644
--- a/src/stages/2-ast_sugar/combinators.ml
+++ b/src/stages/2-ast_sugar/combinators.ml
@@ -129,7 +129,6 @@ let e_annotation ?loc anno_expr ty = make_e ?loc @@ E_ascription {anno_expr; typ
 let e_tuple ?loc lst : expression = make_e ?loc @@ E_tuple lst
 let e_tuple_accessor ?loc tuple path = make_e ?loc @@ E_tuple_accessor {tuple; path}
 let e_tuple_update ?loc tuple path update = make_e ?loc @@ E_tuple_update {tuple; path; update}
-let e_tuple_destruct ?loc tuple fields field_types next = make_e ?loc @@ E_tuple_destruct {tuple; fields; field_types; next}
 let e_pair ?loc a b  : expression = e_tuple ?loc [a;b]
 
 let e_cond ?loc condition then_clause else_clause = make_e ?loc @@ E_cond {condition;then_clause;else_clause}
diff --git a/src/stages/2-ast_sugar/combinators.mli b/src/stages/2-ast_sugar/combinators.mli
index 94529b898..3faebef21 100644
--- a/src/stages/2-ast_sugar/combinators.mli
+++ b/src/stages/2-ast_sugar/combinators.mli
@@ -85,7 +85,6 @@ val e_annotation : ?loc:Location.t -> expression -> type_expression -> expressio
 val e_tuple : ?loc:Location.t -> expression list -> expression
 val e_tuple_accessor : ?loc:Location.t -> expression -> int -> expression
 val e_tuple_update : ?loc:Location.t -> expression -> int -> expression -> expression
-val e_tuple_destruct : ?loc:Location.t -> expression -> expression_variable list -> type_expression list option -> expression -> expression
 val e_pair : ?loc:Location.t -> expression -> expression -> expression
 
 val e_cond: ?loc:Location.t -> expression -> expression -> expression -> expression
diff --git a/src/stages/2-ast_sugar/types.ml b/src/stages/2-ast_sugar/types.ml
index 8c3422de6..88df116fb 100644
--- a/src/stages/2-ast_sugar/types.ml
+++ b/src/stages/2-ast_sugar/types.ml
@@ -77,7 +77,6 @@ and expression_content =
   | E_tuple of expression list
   | E_tuple_accessor of tuple_accessor
   | E_tuple_update   of tuple_update
-  | E_tuple_destruct of tuple_destruct
   (* Data Structures *)
   | E_map of (expression * expression) list 
   | E_big_map of (expression * expression) list
@@ -139,7 +138,6 @@ and sequence = {
 
 and tuple_accessor = {tuple: expression; path: int}
 and tuple_update   = {tuple: expression; path: int ; update: expression}
-and tuple_destruct = {tuple: expression; fields : expression_variable list; field_types : type_expression list option; next : expression}
 
 and environment_element_definition =
   | ED_binder