format left-padding with zero's ?

[Jan Nieuwenhuizen]

What is a nice way to convert a number to a minimum-length string,
left-padded with zeros?

>From the info pages:

       The `format' procedure, to be found in module `(ice-9 format)', can
    do all this, and even more.  If you are a C programmer, you can think
    of this procedure as Guile's `fprintf'.

However:

    $ guile -c '(use-modules (ice-9 format))
    >  (format #t "~s: ~04x\n" (version) 9)'
    "1.7.0":    9
    $ printf '%04x\n' 9
    0009

(yesterday's CVS).
    
Greetings,    
Jan.
-- 
Jan Nieuwenhuizen <address@hidden> | GNU LilyPond - The music typesetter
http://www.xs4all.nl/~jantien       | http://www.lilypond.org