From 81e442958526671f894a97c83aaae6ba982a6cc0 Mon Sep 17 00:00:00 2001
From: Gaith Hallak <gaithhallak@gmail.com>
Date: Thu, 19 Aug 2021 17:09:21 +0300
Subject: [PATCH] Add using namespace parts to scanner and parser

---
 src/aeso_parser.erl | 17 ++++++++++++-----
 src/aeso_scan.erl   |  2 +-
 src/aeso_syntax.erl |  3 ++-
 3 files changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/aeso_parser.erl b/src/aeso_parser.erl
index b5fd8b9..80002ca 100644
--- a/src/aeso_parser.erl
+++ b/src/aeso_parser.erl
@@ -137,12 +137,19 @@ fundef_or_decl() ->
             fundef()]).
 
 using() ->
-    ?RULE(keyword(using), con(), optional({keyword(as), con()}), using(get_ann(_1), _2, _3)).
+    Alias = {keyword(as), con()},
+    For = ?RULE(keyword(for), bracket_list(id()), {for, _2}),
+    Hiding = ?RULE(keyword(hiding), bracket_list(id()), {hiding, _2}),
+    ?RULE(keyword(using), con(), optional(Alias), optional(choice(For, Hiding)), using(get_ann(_1), _2, _3, _4)).
 
-using(Ann, Con, none) ->
-    {using, Ann, Con, none};
-using(Ann, Con, {ok, {_, Alias}}) ->
-    {using, Ann, Con, Alias}.
+using(Ann, Con, none, none) ->
+    {using, Ann, Con, none, none};
+using(Ann, Con, {ok, {_, Alias}}, none) ->
+    {using, Ann, Con, Alias, none};
+using(Ann, Con, none, {ok, List}) ->
+    {using, Ann, Con, none, List};
+using(Ann, Con, {ok, {_, Alias}}, {ok, List}) ->
+    {using, Ann, Con, Alias, List}.
 
 pragma() ->
     Op = choice([token(T) || T <- ['<', '=<', '==', '>=', '>']]),
diff --git a/src/aeso_scan.erl b/src/aeso_scan.erl
index ec47e4f..4587efa 100644
--- a/src/aeso_scan.erl
+++ b/src/aeso_scan.erl
@@ -45,7 +45,7 @@ lexer() ->
 
     Keywords = ["contract", "include", "let", "switch", "type", "record", "datatype", "if", "elif", "else", "function",
                 "stateful", "payable", "true", "false", "mod", "public", "entrypoint", "private", "indexed", "namespace",
-                "interface", "main", "using", "as"
+                "interface", "main", "using", "as", "for", "hiding"
                ],
     KW = string:join(Keywords, "|"),
 
diff --git a/src/aeso_syntax.erl b/src/aeso_syntax.erl
index 5fb02bb..8148a1a 100644
--- a/src/aeso_syntax.erl
+++ b/src/aeso_syntax.erl
@@ -36,6 +36,7 @@
 -type tvar() :: {tvar, ann(), name()}.
 
 -type namespace_alias() :: none | con().
+-type namespace_parts() :: none | {for, [id()]} | {hiding, [id()]}.
 
 -type decl() :: {contract_main, ann(), con(), [decl()]}
               | {contract_child, ann(), con(), [decl()]}
@@ -46,7 +47,7 @@
               | {type_def, ann(), id(), [tvar()], typedef()}
               | {fun_clauses, ann(), id(), type(), [letfun() | fundecl()]}
               | {block, ann(), [decl()]}
-              | {using, ann(), con(), namespace_alias()}
+              | {using, ann(), con(), namespace_alias(), namespace_parts()}
               | fundecl()
               | letfun()
               | letval(). % Only for error msgs