Lexer and parser generators using CTFE

[Hisayuki Mima]

(2012年05月28日 02:31), d coder wrote:
>
>     Generally a parser generated by other tool and accepting tokens
>     returns the abstract syntax tree, but it return the evaluated value
>     in the example.
>     In other words, it does lexical analysis, parsing and (type)
>     converting at a time.
>     If you want simply abstract syntax tree, it may be a little pain to
>     use ctpg.
>
>
>   Hello Youkei
>
> I am trying to use CTPG for compile time parsing for a DSL I am working
> on. I have tried the examples you created in the examples directory.
>
> I would like the parser to effect some side effects. For this purpose, I
> tried including the parser mixin into a class, but I got a strange error
> saying:
>
> Error: need 'this' to access member parse
>
> I have copied the code I am trying to compile at the end of the email.
> Let me know what I could be doing wrong here.
>
> Regards
> - Puneet
>
>
> import ctpg;
> import std.array: join;
> import std.conv: to;
>
> class Foo
> {
>    int result;
>    mixin(generateParsers(q{
>          int root = mulExp $;
>
>          int mulExp =
>            primary !"*" mulExp >> (lhs, rhs){ return lhs * rhs; }
>          / primary;
>
>          int primary = !"(" mulExp !")" / [0-9]+ >> join >> to!int;
>        }));
>
>    void frop() {
>      result = parse!root("5*8");
>    }
> }
>
>
> void main(){
>    Foo foo = new Foo();
>    foo.frop();
> }
>

Hello Puneet,

Thank you for your report. I fixed it. Now CTPG creates a static 
function as a parser.
But I'm afraid this fix doesn't help you because I don't understand what 
a side effect you said is.
Can you show me some examples which include the side effect?

Thanks,
Hisayuki Mima