[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: lexical-binding questions

From: Stefan Monnier
Subject: Re: lexical-binding questions
Date: Tue, 15 May 2012 22:05:36 -0400
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/24.1.50 (gnu/linux)

>>>> (setq lexical-binding t)
>>>> (let ((nil 0)) nil)  => 0
>> Anyway, I guess nil and t should be marked as special-variable-p, if for
>> no other reason than because they are pretty damn special.
> The problem also applies to keyword symbols.

Indeed, except it's a lot less likely that people will try to let-bind
a keyword symbol (it happens to me several times a year to choose `t'
for a variable name, only to find it doesn't work, but I never suffered
from that problem with a keyword symbol).

> I was thinking
>       if (!NILP (lexenv) && SYMBOLP (var)
> +         && !SYMBOL_CONSTANT_P (var)
>         && !XSYMBOL (var)->declared_special
>         && NILP (Fmemq (var, Vinternal_interpreter_environment)))
>       /* Lexically bind VAR by adding it to the lexenv alist.  */
>       lexenv = Fcons (Fcons (var, tem), lexenv);

It would be more efficient to set declared_special on keyword symbols.


reply via email to

[Prev in Thread] Current Thread [Next in Thread]