• Artyom Shalkhakov (73/73) Oct 06 2007 Hello everyone!

Artyom Shalkhakov <artyom.shalkhakov gmail.com> writes:

Hello everyone!

Well, here's what I'm trying to do:

module rtparse;

import Integer = tango.text.convert.Integer;
import Float = tango.text.convert.Float;
import Text = tango.text.Util;

// parse an integer out of string
void parse( T : int, U )( ref int dst, U[] src ) {
	dst = Integer.toInt( src );
}

// generalized parsing function, just a stub
// but if it's not present, DMD complains:
// template parse(T : int, U) does not match any template declaration
// template parse(T : int, U) cannot deduce template function from argument
types (int, char[])
void parse( T, U )( ref T dst, U[] src ) {
//	static if ( is( T == int ) ) {
//		dst = Integer.toInt( src );
//	}
}

struct ParseReturn {
	uint	count;	// count of parsed arguments
	uint	ate;	// characters eaten
}

ParseReturn scanDelimited( T, Args... )( T[] src, T[] set, out Args args ) {
	static assert( is( void function( Args ) ), "scanDelimited :: Args should be a
type tuple" );

	uint	pos, mark;

	T[] get() {
		T[]	token;

		if ( set.length is 1 ) {
			// use fast path if delimiter is a single char
			if ( ( pos = Text.locate( src, set[0], mark ) ) < src.length ) {
				token = src[mark..pos];
				mark = pos + 1;
				return token;
			}
		}
		else if ( set.length > 1 ) {
			foreach ( i, elem; src ) {
				if ( Text.contains( set, elem ) ) {
					token = src[mark..i];
					mark = i + 1;
					return token;
				}
			}
		}
		return src[mark..$];	// NOTE: empty tokens are allowed
	}

	uint	count;

	foreach ( i, arg; args ) {
		T[]	token = get();
		// this calls parse( T, U ) instead of parse( T : int, U )
		parse( arg, token );
		count++;
	}
	return ParseReturn( count, pos );	// beyond return, args are not copied!
}

import tango.io.Stdout;

void main() {
	ParseReturn	r;

	{
		int		a;

		// seems like an issue with tuple and ref/inout/out modifiers
		scanDelimited( "1", ":", a );
                // 'a' doesn't return from the function;
                // in Ddbg, I see that 'arg' value (local in scanDelimited)
                // gets a value of 1, but in this statement, 'a' is 0!
		assert( a == 1 );
	}
        // more tests omitted
}

I'm using tango0.99 RC3 + DMD1.21.

What do I do wrong?

Best regards.