Function: mh-define-obsolete-variable-alias

mh-define-obsolete-variable-alias is a function alias for define-obsolete-variable-alias, defined in byte-run.el.gz.

This macro is obsolete since 29.1; use define-obsolete-variable-alias instead.

Signature

(mh-define-obsolete-variable-alias OBSOLETE-NAME CURRENT-NAME WHEN &optional DOCSTRING)

Documentation

Make OBSOLETE-NAME a variable alias for CURRENT-NAME and mark it obsolete.

WHEN should be a string indicating when the variable was first made obsolete, for example a date or a release number.

This macro evaluates all its parameters, and both OBSOLETE-NAME and CURRENT-NAME should be symbols, so a typical usage would look like:

  (define-obsolete-variable-alias 'foo-thing 'bar-thing "28.1")

This macro uses defvaralias and make-obsolete-variable (which see). See the Info node (elisp)Variable Aliases for more details.

If CURRENT-NAME is a defcustom or a defvar (more generally, any variable where OBSOLETE-NAME may be set, e.g. in an init file, before the alias is defined), then the define-obsolete-variable-alias statement should be evaluated before the defcustom, if user customizations are to be respected. The simplest way to achieve this is to place the alias statement before the defcustom (this is not necessary for aliases that are autoloaded, or in files dumped with Emacs). This is so that any user customizations are applied before the defcustom tries to initialize the variable (this is due to the way defvaralias works).

For the benefit of Customize, if OBSOLETE-NAME has any of the following properties, they are copied to CURRENT-NAME, if it does not already have them: saved-value, saved-variable-comment.

Aliases

mh-define-obsolete-variable-alias (obsolete since 29.1)