Mojo: Add support for constants to the IDL compiler.

mojo/public/tools/bindings/pylib/mojom/parse/parser.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Generates a syntax tree from a Mojo IDL file."""
 
 import imp
 import os.path
 import sys
 
@@ skipping 83 matching lines @@
 
   def p_definitions(self, p):
     """definitions : definition definitions
                    | """
     if len(p) > 1:
       p[0] = _ListFromConcat(p[1], p[2])
 
   def p_definition(self, p):
     """definition : struct
                   | interface
-                  | enum"""
+                  | enum
+                  | const"""
     p[0] = p[1]
 
   def p_attribute_section(self, p):
     """attribute_section : LBRACKET attributes RBRACKET
                          | """
     if len(p) > 3:
       p[0] = p[2]
 
   def p_attributes(self, p):
     """attributes : attribute
                   | attribute COMMA attributes
                   | """
     if len(p) == 2:
       p[0] = _ListFromConcat(p[1])
     elif len(p) > 3:
       p[0] = _ListFromConcat(p[1], p[3])
 
   def p_attribute(self, p):
     """attribute : NAME EQUALS expression
                  | NAME EQUALS NAME"""
     p[0] = ('ATTRIBUTE', p[1], p[3])
 
   def p_struct(self, p):
     """struct : attribute_section STRUCT NAME LBRACE struct_body RBRACE SEMI"""
     p[0] = ('STRUCT', p[3], p[1], p[5])
 
   def p_struct_body(self, p):
     """struct_body : field struct_body
                    | enum struct_body
+                   | const struct_body
                    | """
     if len(p) > 1:
       p[0] = _ListFromConcat(p[1], p[2])
 
   def p_field(self, p):
     """field : typename NAME default ordinal SEMI"""
     p[0] = ('FIELD', p[1], p[2], p[4], p[3])
 
   def p_default(self, p):
     """default : EQUALS expression
                | EQUALS expression_object
                | """
     if len(p) > 2:
       p[0] = p[2]
 
   def p_interface(self, p):
     """interface : attribute_section INTERFACE NAME LBRACE interface_body \
                        RBRACE SEMI"""
     p[0] = ('INTERFACE', p[3], p[1], p[5])
 
   def p_interface_body(self, p):
     """interface_body : method interface_body
                       | enum interface_body
+                      | const interface_body
                       | """
     if len(p) > 1:
       p[0] = _ListFromConcat(p[1], p[2])
 
   def p_response(self, p):
     """response : RESPONSE LPAREN parameters RPAREN
                 | """
     if len(p) > 3:
       p[0] = p[3]
 
@@ skipping 69 matching lines @@
       p[0] = _ListFromConcat(p[1], p[3])
 
   def p_enum_field(self, p):
     """enum_field : NAME
                   | NAME EQUALS expression"""
     if len(p) == 2:
       p[0] = ('ENUM_FIELD', p[1], None)
     else:
       p[0] = ('ENUM_FIELD', p[1], p[3])
 
+  def p_const(self, p):
+    """const : CONST typename NAME EQUALS expression SEMI"""
+    p[0] = ('CONST', p[2], p[3], p[5])
+
   ### Expressions ###
 
   def p_expression_object(self, p):
     """expression_object : expression_array
                          | LBRACE expression_object_elements RBRACE """
     if len(p) < 3:
       p[0] = p[1]
     else:
       p[0] = ('OBJECT', p[2])
 
@@ skipping 96 matching lines @@
 
 def Parse(source, filename):
   lexer = Lexer(filename)
   parser = Parser(lexer, source, filename)
 
   lex.lex(object=lexer)
   yacc.yacc(module=parser, debug=0, write_tables=0)
 
   tree = yacc.parse(source)
   return tree