From: Geert-Jan van Opdorp
Subject: cltl2 format in cltl1 ?
Date: Tue, 08 Aug 1995 00:00:00 +0000
Message-ID: <GEERT.95Aug8171935@sparc.aie.nl>

I'm porting cltl2 code to a system that is
not fully cltl2. The code uses the cltl2 "~/user-function/"
format directive. I was wondering wether there
exists cltl1 code that implements this directive?

Thanks,

Geert-Jan

-- 
Geert-Jan van Opdorp
AI-Engineering
Amsterdam, The Netherlands
·····@aie.nl

From: Barry Margolin
Subject: Re: cltl2 format in cltl1 ?
Date: Wed, 09 Aug 1995 00:00:00 +0000
Message-ID: <40b6is$72q@tools.near.net>

In article <··················@sparc.aie.nl> ·····@sparc.aie.nl (Geert-Jan van Opdorp) writes:
>I'm porting cltl2 code to a system that is
>not fully cltl2. The code uses the cltl2 "~/user-function/"
>format directive. I was wondering wether there
>exists cltl1 code that implements this directive?

I don't think there's a way to add this feature to Common Lisp, since it
has to be built into the FORMAT function (there may be
implementation-dependent ways to extend FORMAT, but you asked for CLtL1
code that does it).  You can often work around it by rewriting the call.

(format stream "~/user-function/")

is equivalent to

(user-function stream nil nil)

If it's embedded in a format string, you can break it up:

(format stream "stuff ~:/user-function/ other stuff" args)

becomes

(progn (format stream "stuff " args used by stuff)
       (user-function stream t nil)
       (format stream " other stuff" args used by other stuff))

It gets more complicated if the ~/user-function/ is embedded in other
constructs, such as ~{...} or ~(...).
-- 
Barry Margolin
BBN PlaNET Corporation, Cambridge, MA
······@bbnplanet.com
Phone (617) 873-3126 - Fax (617) 873-5124