[plt-scheme] SRFI-9 usability issues

From: Bradd W. Szonye (bradd+plt at szonye.com)
Date: Thu Jan 15 15:50:18 EST 2004

Bradd wrote:
>> and EQUAL? can't check two records for deep equality.

Michael Sperber wrote:
> That I think would not be a good idea---

>> SRFI-9 is silent on the issue of printing and comparing records,

> Exactly.  For printing, it doesn't matter.  However, for comparing,
> there's at least one other implementation (Scheme 48) that doesn't do
> deep comparison.  (And, FWIW, Common Lisp doesn't either for DEFSTRUCT
> and EQUAL.)  You implement this, people are going to use it, thus
> creating non-portable code.

Interesting! I'm a bit surprised.

It's not a huge problem. However, it does make records practically
unusable as hash-table keys (which is how I discovered this). For now,
I've switched to using define-struct instead.
-- 
Bradd W. Szonye
http://www.szonye.com/bradd


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