== Revision number ==

A revision number is a small integer.

It is a strictly __local__ ''convenience identifier'' for a [[Revision|revision]].  It can be useful as it is shorter to type than the 40-digit hexadecimal string that uniquely identifies a revision.

=== Common usage ===

Although all files have revision numbers, revision numbers are almost always used to identify a [[ChangeSet|changeset]] within a given [[Repository|repository]].

=== Pitfalls ===

Revision numbers referring to changesets are ''very likely'' to be different in another copy of a repository. ''Do not use them'' to talk about changesets with other people. Use the [[ChangeSetID|changeset ID]] instead.

=== More information ===

The Mercurial command-line client provides much more detailed information on Revision Sets. Just run:

{{{
$ hg help revsets
}}}

=== Notes ===
An empty repository (with no changesets) has a revision number -1, which corresponds to the '''nullid''' [[Nodeid|nodeid]].
For example:
{{{
$ hg log
$ hg status
$ hg head
changeset:   -1:000000000000
tag:         tip
user:
date:        Thu Jan 01 00:00:00 1970 +0000
}}}

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CategoryGlossary

[[FrenchRevisionNumber|Français]]