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Re: Optimising Elisp code

From: Emanuel Berg
Subject: Re: Optimising Elisp code
Date: Fri, 05 Oct 2018 19:23:29 +0200
User-agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4 (gnu/linux)

Óscar Fuentes wrote:

> Emanuel Berg <> writes:
>> OK, in C++ it works like this: If a member
>> function is defined within the class
>> definition (not recommended), or if it is
>> defined outside of it (recommended) with the
>> word "inline" preceding the return type,
>> then the function becomes an inline
>> function. What this means is that when the
>> code is compiled into machine code, instead
>> of having one place for the function, and
>> jumping back and forth every time that
>> function is called, the machine code for the
>> inline function is placed, duplicated
>> wherever it is used. So you get longer
>> machine code, but faster, since there is
>> just constant execution for the inline
>> functions, without jumping back and forth.
>> When should it be used? If the function is
>> very short, say 1-3 lines, the jumping back
>> and forth requires more machine instructions
>> than the function itself. Then the
>> organizational gain of having it neatly at
>> one place is diminished by the speed
>> advantage of not having to jump back and
>> forth to that place all the time.
> Just in case any bystander finds this post:
> don't rely on anything that is mentioned
> above, nor for C++ `inline' keyword nor for
> code inlining in general.

I read it in this book:

      author     = {Jan Skansholm},
      ISBN       = {91-44-47931-X},
      publisher  = {Studentlitteratur},
      title      = {C++ direkt},
      year       = {1996}

underground experts united

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