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Re: Are two symbols `equal' iff they are `eq'?
From: |
Marcin Borkowski |
Subject: |
Re: Are two symbols `equal' iff they are `eq'? |
Date: |
Sun, 09 Aug 2015 17:46:54 +0200 |
On 2015-08-09, at 17:28, Drew Adams <drew.adams@oracle.com> wrote:
>> As in the subject; neither the manual nor the docstring for `equal'
>> are very clear on this. (The docstring for `equal' says: "Symbols must
>> match exactly.", which -- I would guess -- means `eq', but I'm not
>> sure.)
>
> Yes. `equal' requires symbols to have the same name, value,
> function definition, and plist, and to be interned in the same
> obarray. They need to be the same Lisp object (a symbol).
>
> In sum: they need to be `eq'.
Do I get it right that for two symbols to be `eq' it is enough for them
to have the same name and to be interned in the same obarray?
> Emacs Lisp doesn't have a spec (just its code, and some doc).
> But this is what the Common Lisp spec says about `equal' for
> symbols:
>
> Returns true if x and y are structurally similar (isomorphic)
> objects. Objects are treated as follows by equal.
>
> * Symbols, Numbers, and Characters
> equal is true of two objects if they are symbols that are eq,
> ^^^^^^^^^^^^^^^^^^^
> if they are numbers that are eql, or if they are characters
> that are eql.
Thanks,
--
Marcin Borkowski
http://octd.wmi.amu.edu.pl/en/Marcin_Borkowski
Faculty of Mathematics and Computer Science
Adam Mickiewicz University
- Re: Are two symbols `equal' iff they are `eq'?, Joost Kremers, 2015/08/08
- Re: Are two symbols `equal' iff they are `eq'?, Ian Zimmerman, 2015/08/09
- Re: Are two symbols `equal' iff they are `eq'?, Marcin Borkowski, 2015/08/09
- Re: Are two symbols `equal' iff they are `eq'?, Michael Heerdegen, 2015/08/09
- Re: Are two symbols `equal' iff they are `eq'?, Marcin Borkowski, 2015/08/09
- Re: Are two symbols `equal' iff they are `eq'?, Eli Zaretskii, 2015/08/09
- Re: Are two symbols `equal' iff they are `eq'?, Marcin Borkowski, 2015/08/09
- Re: Are two symbols `equal' iff they are `eq'?, Eli Zaretskii, 2015/08/09