Overview

Anaphoric expressions for Emacs Lisp, providing implicit temporary variables.

• Quickstart
• anaphora
• See Also
• Notes
• Compatibility and Requirements

Quickstart

(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)))))

;; to fontify `it' and `self'
(with-eval-after-load "lisp-mode"
  (anaphora-install-font-lock-keywords))

anaphora

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:

(require 'anaphora)

The following macros are made available

aand
ablock
acase
acond
aecase
aetypecase
apcase
aif
alambda
alet
aprog1
aprog2
atypecase
awhen
awhile
a+
a-
a*
a/

The following macros are experimental

anaphoric-set
anaphoric-setq

See Also

• http://en.wikipedia.org/wiki/Anaphoric_macro

Notes

Partially 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

GNU Emacs version 26.1           : yes
GNU Emacs version 25.x           : yes
GNU Emacs version 24.x           : yes
GNU Emacs version 23.x           : yes
GNU Emacs version 22.x           : yes
GNU Emacs version 21.x and lower : unknown

No external dependencies