inhibit-changing-match-data

inhibit-changing-match-data is a variable defined in `C source code'.
Its value is

nil

Documentation:
Internal use only.
If non-nil, the primitive searching and matching functions
such as `looking-at', `string-match', `re-search-forward', etc.,
do not set the match data. The proper way to use this variable
is to bind it with `let' around a small expression.