nano: Search and Replace
3.6 Search and Replace
======================
One can search the current buffer for the occurrence of any string with
the Search command (default key binding: ‘^W’). The default search mode
is forward, case-insensitive, and for literal strings. But one can
search backwards by pressing ‘M-B’, search case sensitively with ‘M-C’,
and interpret regular expressions in the search string with ‘M-R’.
A regular expression in a search string always covers just one line;
it cannot span multiple lines. And when replacing (with ‘^\’ or ‘M-R’)
the replacement string cannot contain a newline (LF).