From 99e9fc7de57f762560ebc75097ff1f9c6b20fecc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Bart=C5=82omiej=20Pluta?= <the.orleander@gmail.com>
Date: Sat, 6 Jul 2019 23:08:12 +0200
Subject: [PATCH] Create Parser.optional() helper method

---
 smnp/ast/node/type.py | 11 ++---------
 smnp/ast/parser.py    | 12 ++++++++++++
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/smnp/ast/node/type.py b/smnp/ast/node/type.py
index d2a07d1..4612f09 100644
--- a/smnp/ast/node/type.py
+++ b/smnp/ast/node/type.py
@@ -42,13 +42,6 @@ class TypeNode(AccessNode):
 
     @classmethod
     def _parse(cls, input):
-        return Parser.oneOf(
-            cls._specifiedTypeParser(),
-            cls._rawTypeParser()
-        )(input)
-
-    @classmethod
-    def _specifiedTypeParser(cls):
         def createNode(type, specifier):
             node = TypeNode(type.pos)
             node.type = type.value
@@ -57,9 +50,9 @@ class TypeNode(AccessNode):
 
         return Parser.allOf(
             cls._rawTypeParser(),
-            TypeSpecifier.parse,
+            Parser.optional(TypeSpecifier.parse),
             createNode=createNode
-        )
+        )(input)
 
     @classmethod
     def _rawTypeParser(cls):
diff --git a/smnp/ast/parser.py b/smnp/ast/parser.py
index 96198f3..746cc66 100644
--- a/smnp/ast/parser.py
+++ b/smnp/ast/parser.py
@@ -1,5 +1,6 @@
 from smnp.ast.node.ignore import IgnoredNode
 from smnp.ast.node.model import ParseResult, Node
+from smnp.ast.node.none import NoneNode
 from smnp.error.syntax import SyntaxException
 
 
@@ -139,3 +140,14 @@ class Parser:
             return result
 
         return parse
+
+    @staticmethod
+    def optional(parser):
+        def parse(input):
+            result = parser(input)
+            if result.result:
+                return result
+
+            return ParseResult.OK(NoneNode())
+
+        return parse