Re: elisp question: format

[Kevin Rodgers <kevin.d.rodgers@gmail.com>]

Aaron Maxwell wrote:
> Hi,
> 
> Is there a way to direct the format function to use a single value
> repeatedly for several positional parameters?
> 
> Here's the specific example of what I mean.  In my .emacs, the
> following string is used:
> "/home/amax/opt/scmutils/mit-scheme/bin/scheme --band /home/amax/opt/scmutils/mit-scheme/lib/edwin-mechanics.com --heap 6000 --library /home/amax/opt/scmutils/mit-scheme/lib"
> 
> (See [1] if you're curious what it's for.)  The substring "/home/amax/opt/scmutils/mit-scheme" repeats 3 times. The idea I had is to use a format string like:
> 
> (format "%s/bin/scheme --band %s/lib/edwin-mechanics.com --heap 6000 --library %s/lib" ...(something)...)
> 
> ... and to do this in a way that I only had to type that substring
> once.  However, I did not find a way to do this directly.  The closest
> thing I came up with is this:
> 
> (apply 'format 
>        (cons "%s/bin/scheme --band %s/lib/edwin-mechanics.com --heap 6000 --library %s/lib" 
>        (make-list 3 "/home/amax/opt/scmutils/mit-scheme")))
> 
> Is there a clearer way to do this? 

(let ((scheme-home "/home/amax/opt/scmutils/mit-scheme"))
   (format "%s/bin/scheme --band %s/lib/edwin-mechanics.com --heap 6000 
--library %s/lib"
	  scheme-home scheme-home scheme-home))

-- 
Kevin Rodgers
Denver, Colorado, USA