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Re: Format strings are wrong
> From: Charles Stewart <cas@xxxxxxxxxxxxxxxxxxxxxxxxx>
> Specific points and criticisms:
> 1. I think single letter escapes are fine: like mathematical
> constants if you use or often read them, you'll remember them.
> However, I would like it to be the case that you don't need to have
> memorised the whole table to be able to tell consuming escapes from
> non-consuming escapes (eg. upper case vs. lower case, alphnumeric vs.
> 2. Is it good to have both ~? and ~K: why have backward compatibility
> cruft in the first SRFI? Explanation, please!
You probably need a better Lisp historian than I, but I believe most early
Lisps (spelled LISPs then) inherited some form of FORMAT function from
MACLISP [MIT/LCS/TT-295, The Revised Maclisp Manual, circa 1983 is the
earliest reference I have]. I wrote a bunch of code in T and Scheme48 at
various times and implemented a FORMAT function in 1988(?) which I ported to
most Scheme's which did not have one. SLIB picked up this version which was
then generalized to the current CL "kitchen sink".
So one reason is that I am old and crufty enough to remember/use/rewrite a
bunch of old code.
Another reason is to reserve "K" as a dispatch character to avoid breaking old
code. SLIB does this as well (but probably inherited from my code).
Personally, I don't use "~K", so am happy to drop it. Note, however, that
SLIB also allows "~K", so why not reserve it?
[As an exercise, you might take, e.g. Scheme48, search/grep for all uses of
"format", and replace them with a new convention. Get a concensus on the
conventions, do the for all existing implementations which use some form of
format currently and ... Just kidding. Pick a new name and make your
proposal. Blame MacLisp! 8^]
> 3. It seems to me the nicest functional formatter uses the standard
> string concatenater together with quasiquotation.
As an implementor I don't think writing characters to a port should be held
hostage to string concatenation. You are welcome to supply your own