'<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,
+'<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}\{tag\}' can be used to ensure that 'rev' identifies an
+'<rev>{caret}\{tag\}' can be used to ensure that '<rev>' identifies an
existing tag object.
'<rev>{caret}{}', e.g. 'v0.99.8{caret}{}'::