Doc: add index entry "brackets" for parentheses

diff --git a/Documentation/notation/editorial.itely b/Documentation/notation/editorial.itely
index 0f7c96a5878374260dd8cf8e57b7a5f83cbdd5f0..c035dc2d5c1a3d81978be2382af8526a7d532399 100644 (file)
--- a/Documentation/notation/editorial.itely
+++ b/Documentation/notation/editorial.itely
@@ -398,6 +398,7 @@ Notes in a chord cannot be colored with @code{\override}; use
 @cindex notes, ghost
 @cindex notes, parenthesized
 @cindex parentheses
+@cindex brackets
 
 @funindex \parenthesize
 @funindex parenthesize