summaryrefslogtreecommitdiff
path: root/lisp/emacs-lisp
diff options
context:
space:
mode:
Diffstat (limited to 'lisp/emacs-lisp')
-rw-r--r--lisp/emacs-lisp/re-builder.el17
1 files changed, 16 insertions, 1 deletions
diff --git a/lisp/emacs-lisp/re-builder.el b/lisp/emacs-lisp/re-builder.el
index c5307f70d08..1fc6c872332 100644
--- a/lisp/emacs-lisp/re-builder.el
+++ b/lisp/emacs-lisp/re-builder.el
@@ -485,7 +485,22 @@ If the optional PAUSE is non-nil then pause at the end in any case."
(defun reb-change-syntax (&optional syntax)
"Change the syntax used by the RE Builder.
-Optional argument SYNTAX must be specified if called non-interactively."
+Interactively, prompt for SYNTAX.
+
+Re-Builder currently understands three different forms of input, namely
+`read', `string', and `rx' syntax:
+
+ 1. The `string' syntax is the same one used by functions such as
+ `query-replace-regexp' (\\[query-replace-regexp]). There is no need to escape
+ backslashes and double quotes.
+
+ 2. The `read' syntax is the same syntax used as when specifying the
+ regexp as a string in a Lisp program.
+
+ 3. Finally, the `rx' syntax allows editing of symbolic regular
+ expressions supported by the package of the same name.
+
+When called from Lisp, SYNTAX must be specified."
(interactive
(list (intern
(completing-read