[Order of arguments to sequence :TEST functions]

[Randy%acorn@oak.lcs.mit.edu]

> Date: Mon, 29 Feb 88 09:34 EST
> From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
> Subject: Order of arguments to sequence :TEST functions
> To: common-lisp@sail.stanford.edu
> 
> CLtL page 247 says
> 	... (funcall testfn item (keyfn x)) ...
> I'm curious to know why this order was chosen instead of
> 	... (funcall testfn (keyfn x) item) ...
>  ...
> Yes, I know I can use find-if, and that's what I'm really doing.  Was
> there a reason for the ordering choice?  Does anybody depend on it, or
> know of somebody that does?  Is there any chance of CLtL'89 reversing
> it (and documenting the reason in the text)?

It seems that anyone who does

(FIND number list-of-number :test #'<) 

is depending on the order of the arguments to the test.  I don't
know for sure if anyone depends on this, but it doesn't seem like
a particularly contorted example.  There are a fair number of
non-commutative predicates.

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