Anaphoric expressions for Emacs Lisp, providing implicit temporary variables.
(require 'anaphora) (awhen (big-long-calculation) (foo it) ; `it` is provided as (bar it)) ; a temporary variable ;; anonymous function to compute factorial using `self` (alambda (x) (if (= x 0) 1 (* x (self (1- x)))))
Anaphoric expressions implicitly create one or more temporary variables which can be referred to during the expression. This technique can improve clarity in certain cases. It also enables recursion for anonymous functions.
To use anaphora, place the anaphora.el library somewhere Emacs can find it, and add the following to your ~/.emacs file:
The following macros are made available
aand ablock acase acond aecase aetypecase aif alambda alet aprog1 atypecase awhen awhile a+ a- a* a/
Principally based on examples from the book "On Lisp", by Paul Graham.
When this library is loaded, the provided anaphoric forms are registered as keywords in font-lock. This may be disabled via customize.
Compatibility and Requirements
Tested on GNU Emacs versions 23.3 and 24.1
No external dependencies