ido: Regexp Matching
2.4 Regular Expression Matching
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There is limited provision for regexp matching within Ido, enabled
through ‘ido-enable-regexp’ (toggle with ‘C-t’). This allows you to
type ‘[ch]$’ for example and see all file names ending in ‘c’ or ‘h’.
-- User Option: ido-enable-regexp
If the value of this user option is non-‘nil’, Ido will do regexp
matching. The value of this user option can be toggled within
ido-mode using ‘ido-toggle-regexp’.
*Please notice:* Ido-style completion is inhibited when you enable
regexp matching.