[Top][All Lists]

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

Re: no empty (zero) string predicate in Elisp

From: Stefan Monnier
Subject: Re: no empty (zero) string predicate in Elisp
Date: Sun, 26 Apr 2015 17:25:47 -0400
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/25.0.50 (gnu/linux)

> This is exactly what I'm pointing to!  If you want to consider how elisp
> intgers are encoded on the native machine, then you definitely want a
> zerop function, because there are BEQ and SEQ instructions.

But that's not the case: Elisp is compiled to Emacs's byte-code
"machine" which does not have such instructions.

> Not in emacs-version "24.3.1"  where I produced the disassembly
> provided.  But I'm happy to see it being optimized, this is one more
> reason to keep it and use it.

Indeed, the inefficiency of zerop was pointed out "recently" and has
I think it's only fixed in Emacs-25.


reply via email to

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