Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Showing content from https://www.gnu.org/software/emacs/manual/html_node/elisp/Compilation-Tips.html below:

Compilation Tips (GNU Emacs Lisp Reference Manual)

Next: Tips for Avoiding Compiler Warnings, Previous: Emacs Programming Tips, Up: Tips and Conventions   [Contents][Index]

Here are ways of improving the execution speed of byte-compiled Lisp programs.

• Profile your program, to find out where the time is being spent. See Profiling.
• Use iteration rather than recursion whenever possible. Function calls are slow in Emacs Lisp even when a compiled function is calling another compiled function.
• Using the primitive list-searching functions memq, member, assq, or assoc is even faster than explicit iteration. It can be worth rearranging a data structure so that one of these primitive search functions can be used.
• Certain built-in functions are handled specially in byte-compiled code, avoiding the need for an ordinary function call. It is a good idea to use these functions rather than alternatives. To see whether a function is handled specially by the compiler, examine its byte-compile property. If the property is non-nil, then the function is handled specially.

  For example, the following input will show you that aref is compiled specially (see Functions that Operate on Arrays):

  (get 'aref 'byte-compile)
       ⇒ byte-compile-two-args
  

  Note that in this case (and many others), you must first load the bytecomp library, which defines the byte-compile property.

• If calling a small function accounts for a substantial part of your program’s running time, make the function inline. This eliminates the function call overhead. Since making a function inline reduces the flexibility of changing the program, don’t do it unless it gives a noticeable speedup in something slow enough that users care about the speed. See Inline Functions.

RetroSearch is an open source project built by @garambo | Open a GitHub Issue

Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo

HTML: 3.2 | Encoding: UTF-8 | Version: 0.7.4