Re: Guile regular expressions are too greedy [Solved]

[Chris Dennis]

Peter Brett wrote:
> Chris Dennis <address@hidden> writes:
>
> > Hello Guile People
> >
> > Is there a way to make Guile regular expressions less greedy?  I
> > understand that POSIX doesn't define non-greedy modifiers.
> >
> > Specifically, I'm trying to parse font names such as
> >
> >     Arial 12
> >     Arial Bold Italic 14
> >     Nimbus Sans L Bold Italic Condensed 11
> >
> > so that I can construct CSS styles from them.
> >
> > I've tried the following, but the first (.*) gobbles up everything
> > before the size because the other elements are optional:
> >
> > (define s (string-match "(.*)( +(bold|semi-bold|regular|light))?(
> > +(italic|oblique))?( +(condensed))? +([0-9]+)" "nimbus sans l bold
> > italic condensed 11"))
> >
> >
> > Are there other ways of doing this?
>
> Does this work for you?
>
> (define (parsefont str)
>   (let ((match (string-match "( +(bold|semi-bold|regular|light))?( 
> +(italic|oblique))?( +(condensed))? +([0-9]+)" str)))
>     (cons (match:prefix match)
>           (map (lambda (n) (match:substring match n)) '(2 4 6 7)))))
>
> (parsefont "nimbus sans l bold italic condensed 11")
>
> ==> ("nimbus sans l" "bold" "italic" "condensed" "11")
>
> HTH,
>
>                                      Peter

Brilliant!  I was just about to give up on regular expressions and write 
some tedious string-manipulation code.  That works perfectly.  Thank you 
very much.

(That code will now become part of GnuCash).

cheers

Chris

--
Chris Dennis                                  address@hidden
Fordingbridge, Hampshire, UK