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Subject: |
[PATCH] Misleading `list-get' argument description |
Date: |
Tue, 9 Apr 2019 12:34:09 +0200 |
The doc string for `list-get' says
Use TESTFN to lookup in the alist if non-nil. Otherwise, use `assq'.
which is misleading since it's an equality predicate, not a look-up function,
and the default is `eq', not `assq'.
How about changing it to
Equality is defined by TESTFN or by `eq' if nil or omitted.
0001-Clarify-the-TESTFN-argument-to-alist-get.patch
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Subject: |
Re: bug#35206: [PATCH] Misleading `list-get' argument description |
Date: |
Tue, 9 Apr 2019 16:59:48 +0200 |
9 apr. 2019 kl. 16.41 skrev Eli Zaretskii <address@hidden>:
>
> Find an element of ALIST whose `car' equals KEY and return its `cdr'.
> ...
> Equality with KEY is tested by TESTFN, defaulting to `eq'.
Thank you, I pushed that change (except that I used "the first element" instead
of "an element" for precision).
> IMO, this isn't about assuming knowledge, this is about being as
> explicit as reasonably possible about what the function does.
> (Strictly speaking, both your suggestion and mine still assume some
> knowledge about alists, because we never explain what is an alist, nor
> what is an "element" of an alist.)
That's all right -- I was mainly concerned with the quite misleading TESTFN
description, and looked at the docs of similar functions (assq, assoc).
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