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A revision parameter '<rev>' typically, but not necessarily, names a
-commit object. It uses what is called an 'extended SHA1'
+commit object. It uses what is called an 'extended SHA-1'
syntax. Here are various ways to spell object names. The
ones listed near the end of this list name trees and
blobs contained in a commit.
'<sha1>', e.g. 'dae86e1950b1277e545cee180551750029cfe735', 'dae86e'::
- The full SHA1 object name (40-byte hexadecimal string), or
+ The full SHA-1 object name (40-byte hexadecimal string), or
a leading substring that is unique within the repository.
E.g. dae86e1950b1277e545cee180551750029cfe735 and dae86e both
name the same commit object if there is no other object in
'<rev>{caret}\{<type>\}', e.g. 'v0.99.8{caret}\{commit\}'::
A suffix '{caret}' followed by an object type name enclosed in
- brace pair 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'
+ brace pair means dereference the object at '<rev>' recursively until
+ an object of type '<type>' is found or the object cannot be
+ dereferenced anymore (in which case, barf).
+ For example, if '<rev>' is a commit-ish, '<rev>{caret}\{commit\}'
+ describes the corresponding commit object.
+ Similarly, if '<rev>' is a tree-ish, '<rev>{caret}\{tree\}'
+ describes the corresponding tree object.
+ '<rev>{caret}0'
is a short-hand for '<rev>{caret}\{commit\}'.
++
+'rev{caret}\{object\}' can be used to make sure 'rev' names an
+object that exists, without requiring 'rev' to be a tag, and
+without dereferencing 'rev'; because a tag is already an object,
+it does not have to be dereferenced even once to get to an object.
'<rev>{caret}\{\}', e.g. 'v0.99.8{caret}\{\}'::
A suffix '{caret}' followed by an empty brace pair
'<rev1>..<rev2>'::
Include commits that are reachable from <rev2> but exclude
- those that are reachable from <rev1>.
+ those that are reachable from <rev1>. When either <rev1> or
+ <rev2> is omitted, it defaults to 'HEAD'.
'<rev1>\...<rev2>'::
Include commits that are reachable from either <rev1> or
- <rev2> but exclude those that are reachable from both.
+ <rev2> but exclude those that are reachable from both. When
+ either <rev1> or <rev2> is omitted, it defaults to 'HEAD'.
'<rev>{caret}@', e.g. 'HEAD{caret}@'::
A suffix '{caret}' followed by an at sign is the same as listing