C.parse() keeps internal state

[ghazel]

C.parse seems to keep state somewhere, which breaks the ability to parse more than once;

1.9.3p286 :001 > require 'cast'
 => true 
1.9.3p286 :002 > C.parse("typedef int fun;")
 => TranslationUnit
    entities: 
        - Declaration
            storage: typedef
            type: Int
            declarators: 
                - Declarator
                    name: "fun"

1.9.3p286 :003 > C.parse("typedef int fun;")
C::ParseError: 1:0: invalid type specifier combination: int fun
    from c.y:593:in `parse'
    from cast-0.2.1/lib/cast/parse.rb:57:in `parse'
    from cast-0.2.1/lib/cast/parse.rb:51:in `parse'
    from (irb):3
    from ruby-1.9.3-p286/bin/irb:16:in `<main>'

[oggy]

Yes, as noted in the readme, C parsers need to keep the list of type names as part of their state. Seems like it's useful behavior not to flush this state between parses - it means you can add some type names to the default parser, then parse all the snippets you want. I'm open to being convinced otherwise, but the behavior is intentional.

If you want to control state explicitly, you can instantiate your own parser (C::Parser.new). You can also pass this to the various snippet parsing methods:

2.1.0 :002 > parser = C::Parser.new
 => #<C::Parser:0x00000101f87120 @type_names=#<Set: {}>, @warning_proc=#<Proc:0x00000101f87008@c.y:579 (lambda)>, @pos=#<C::Node::Pos:0x00000101f86fe0 @filename=nil, @line_num=1, @col_num=0>> 
2.1.0 :003 > parser.type_names << 'Thing'
 => #<Set: {"Thing"}> 
2.1.0 :004 > C::Declaration.parse('Thing t;', parser)
 => Declaration
    type: CustomType
        name: "Thing"
    declarators: 
        - Declarator
            name: "t"

[ghazel]

I would expect module / class methods to keep no state, and the C::Parser.new approach to be used when state should be kept on that object.

[oggy]

Ok, I'm convinced. :)