ref-format documentation.

Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 15 insertions, 2 deletions

diff --git a/Documentation/git-rev-parse.txt b/Documentation/git-rev-parse.txt
index 694f3a09d4..099db294f4 100644
--- a/Documentation/git-rev-parse.txt
+++ b/Documentation/git-rev-parse.txt
@@ -79,8 +79,9 @@ OPTIONS
 SPECIFYING REVISIONS
 --------------------
 
-A revision parameter typically names a commit object.  They use
-what is called an 'extended SHA1' syntax.
+A revision parameter typically, but not necessarily, names a
+commit object.  They use what is called an 'extended SHA1'
+syntax.
 
 * The full SHA1 object name (40-byte hexadecimal string), or
   a substring of such that is unique within the repository.
@@ -106,6 +107,18 @@ what is called an 'extended SHA1' syntax.
   equivalent to rev{caret}{caret}{caret} which is equivalent to\
   rev{caret}1{caret}1{caret}1.
 
+* A suffix '{caret}' followed by an object type name enclosed in
+  brace pair (e.g. `v0.99.8{caret}\{commit\}`) means the object
+  could be a tag, and dereference the tag recursively until an
+  object of that type is found or the object cannot be
+  dereferenced anymore (in which case, barf).  `rev{caret}0`
+  introduced earlier is a short-hand for `rev{caret}\{commit\}`.
+
+* A suffix '{caret}' followed by an empty brace pair
+  (e.g. `v0.99.8{caret}\{\}`) means the object could be a tag,
+  and dereference the tag recursively until a non-tag object is
+  found.
+
 'git-rev-parse' also accepts a prefix '{caret}' to revision parameter,
 which is passed to 'git-rev-list'.  Two revision parameters
 concatenated with '..' is a short-hand for writing a range