Re: Any interest for a parser class?

From: rogeeff (rogeeff_at_[hidden])
Date: 2002-01-17 15:25:24

--- In boost_at_y..., "joel de guzman" <djowel_at_g...> wrote:
> 
[...]
> 
> Ok here's a quick shot at it:
> Borland 5.5.1
> 
> ////////////////////////////////////////////////////////////////////
///////////
> Hand coded {based on Gennadiy's code}: 
> 181K {includes main driver code}

25k using MSVCSP5; release mode.

> 
> bool
> parse_complex(char const* in, double& r, double& i)
> {
>     //  parses complex numbers of the form r or (r) or (r,i)
> 
>     tokenizer<> tok(in, in+strlen(in));
>     tokenizer<>::iterator iter=tok.begin();
> 
>     r = lexical_cast<double>(*iter++);
>     i = lexical_cast<double>(*iter);
> }
> 
> Note: This code allows improper syntax such as "(((1,,,()(2)((("
> Needless to say, adding more code to conform to the 
> grammar will increase the code size.

Not signiifcantly (using returnable delimeters). More over sometimes 
I would not want tight semantic defined in your implementation.

[...]

> Cheers,
> --Joel