Tags: patch


Before d50c82f3e98e ("Simplify
'help-enable-variable-value-editing' using 'string-edit'"),
help-fns-edit-variable would open a buffer in emacs-lisp-mode
and would not allow exiting that buffer with an invalid Lisp
expression.  Restore that functionality by enhancing string-edit
to allow choosing a major mode and allow passing a function to
validate the buffer contents before returning.

In GNU Emacs 30.1.50 (build 8, x86_64-pc-linux-gnu, X toolkit, cairo
 version 1.15.12, Xaw scroll bars) of 2025-04-10 built on
 igm-qws-u22796a
Repository revision: 128bc06bfcc56a35d6b5555cc546faaf0d964df0
Repository branch: emacs-30
Windowing system distributor 'The X.Org Foundation', version 11.0.12011000
System Description: Rocky Linux 8.10 (Green Obsidian)

Configured using:
 'configure --config-cache --with-x-toolkit=lucid --without-gpm
 --without-gconf --without-selinux --without-imagemagick --with-modules
 --with-gif=no --with-cairo --with-rsvg --without-compress-install
 --with-tree-sitter --with-native-compilation=aot'