Document bug in `replace-regexp-in-string'

`replace-regexp-in-string' omits the first START characters of the
input string in its return value.  This is a clear bug, but fixing it
probably causes more trouble; document the behaviour instead (bug#36372).

* doc/lispref/searching.texi (Search and Replace)
* lisp/subr.el (replace-regexp-in-string):
Document current behaviour.

1 files changed, 2 insertions, 1 deletions

diff --git a/lisp/subr.el b/lisp/subr.el
index baff1e909a1..b981af6afe6 100644
--- a/lisp/subr.el
+++ b/lisp/subr.el
@@ -4208,7 +4208,8 @@ Return a new string containing the replacements.
 
 Optional arguments FIXEDCASE, LITERAL and SUBEXP are like the
 arguments with the same names of function `replace-match'.  If START
-is non-nil, start replacements at that index in STRING.
+is non-nil, start replacements at that index in STRING, and omit
+the first START characters of STRING from the return value.
 
 REP is either a string used as the NEWTEXT arg of `replace-match' or a
 function.  If it is a function, it is called with the actual text of each