Emacs provides several commands for performing search-and-replace
operations. In addition to the simple M-x replace-string
command, there is M-% (
query-replace), which presents
each occurrence of the pattern and asks you whether to replace it.
The replace commands normally operate on the text from point to the
end of the buffer. When the region is active, they operate on it
instead (see Mark). The basic replace commands replace one
search string (or regexp) with one replacement string. It
is possible to perform several replacements in parallel, using the
expand-region-abbrevs (see Expanding Abbrevs).
Unlike incremental search, the replacement commands do not use lax
space matching (see Special Isearch) by default. To enable lax
space matching for replacement, change the variable
t. (This only affects how
Emacs finds the text to replace, not the replacement text.)