From 88139fe99c281c21e7090644ac2867b36e1e5a3e Mon Sep 17 00:00:00 2001
From: Ulf Norell <ulf.norell@gmail.com>
Date: Fri, 26 Apr 2019 13:35:35 +0200
Subject: [PATCH] Get rid of unit in AST

---
 src/aeso_ast_infer_types.erl | 2 --
 src/aeso_parser.erl          | 4 +---
 src/aeso_pretty.erl          | 1 -
 src/aeso_syntax.erl          | 1 -
 4 files changed, 1 insertion(+), 7 deletions(-)

diff --git a/src/aeso_ast_infer_types.erl b/src/aeso_ast_infer_types.erl
index 324def0..f157eb7 100644
--- a/src/aeso_ast_infer_types.erl
+++ b/src/aeso_ast_infer_types.erl
@@ -938,8 +938,6 @@ infer_expr(Env, Id = {Tag, As, _}) when Tag == id; Tag == qid ->
 infer_expr(Env, Id = {Tag, As, _}) when Tag == con; Tag == qcon ->
     {QName, Type} = lookup_name(Env, As, Id, [freshen]),
     {typed, As, QName, Type};
-infer_expr(Env, {unit, As}) ->
-    infer_expr(Env, {tuple, As, []});
 infer_expr(Env, {tuple, As, Cpts}) ->
     NewCpts = [infer_expr(Env, C) || C <- Cpts],
     CptTypes = [T || {typed, _, _, T} <- NewCpts],
diff --git a/src/aeso_parser.erl b/src/aeso_parser.erl
index c174a6b..ba9e8b9 100644
--- a/src/aeso_parser.erl
+++ b/src/aeso_parser.erl
@@ -441,7 +441,7 @@ build_if(Ann, Cond, Then, [{elif, Ann1, Cond1, Then1} | Elses]) ->
 build_if(Ann, Cond, Then, [{else, _Ann, Else}]) ->
     {'if', Ann, Cond, Then, Else};
 build_if(Ann, Cond, Then, []) ->
-    {'if', Ann, Cond, Then, {unit, [{origin, system}]}}.
+    {'if', Ann, Cond, Then, {tuple, [{origin, system}], []}}.
 
 else_branches([Elif = {elif, _, _, _} | Stmts], Acc) ->
     else_branches(Stmts, [Elif | Acc]);
@@ -457,7 +457,6 @@ fun_t(Domains, Type) ->
     lists:foldr(fun({Dom, Ann}, T) -> {fun_t, Ann, [], Dom, T} end,
                 Type, Domains).
 
-tuple_e(Ann, [])      -> {unit, Ann};
 tuple_e(_Ann, [Expr]) -> Expr;  %% Not a tuple
 tuple_e(Ann, Exprs)   -> {tuple, Ann, Exprs}.
 
@@ -478,7 +477,6 @@ parse_pattern({record, Ann, Fs}) ->
     {record, Ann, lists:map(fun parse_field_pattern/1, Fs)};
 parse_pattern(E = {con, _, _})    -> E;
 parse_pattern(E = {id, _, _})     -> E;
-parse_pattern(E = {unit, _})      -> E;
 parse_pattern(E = {int, _, _})    -> E;
 parse_pattern(E = {bool, _, _})   -> E;
 parse_pattern(E = {bytes, _, _})  -> E;
diff --git a/src/aeso_pretty.erl b/src/aeso_pretty.erl
index 8a09fbc..3177e60 100644
--- a/src/aeso_pretty.erl
+++ b/src/aeso_pretty.erl
@@ -332,7 +332,6 @@ expr_p(_, {Type, _, Bin})
          Type == oracle_pubkey;
          Type == oracle_query_id ->
     text(binary_to_list(aeser_api_encoder:encode(Type, Bin)));
-expr_p(_, {unit, _}) -> text("()");
 expr_p(_, {string, _, S}) -> term(binary_to_list(S));
 expr_p(_, {char, _, C}) ->
     case C of
diff --git a/src/aeso_syntax.erl b/src/aeso_syntax.erl
index 25f0963..63f192d 100644
--- a/src/aeso_syntax.erl
+++ b/src/aeso_syntax.erl
@@ -75,7 +75,6 @@
      | {contract_pubkey, binary()}
      | {oracle_pubkey, binary()}
      | {oracle_query_id, binary()}
-     | {unit, ann()}
      | {string, ann(), binary()}
      | {char, ann(), integer()}.