Aliases are helpful to shorten long commands that you use often. Take for example the log command. Running bzr log without parameters in large projects would produce an awful lot of an output, so it is compulsory to add the --limit parameter. Furthermore, the default output format is long. This may be too much detail for everyday use, and the single-line format may be informative enough for most purposes. Thus, we end up with, for example, the following:

$ bzr log --limit 5 --line

This is rather long to type if you use it often. Luckily, we can shorten it with an alias; let's call it l5, as follows:

$ bzr alias l5='log --limit 5 --line'

You can use aliases as if they were Bazaar commands. For example:

$ bzr l5 lp:bzr
6573: Patch Queue Manager 2013-02-07 [merge] (jameinel) Fix bug #1107464,      
6572: Patch Queue Manager 2012-12-10 [merge] (vila) Fix LC_ALL=C test failur...
6571: Patch Queue Manager 2012-10-25 [merge] (gz) Set approved revision and ...
6570: Patch Queue Manager 2012-10-14 [merge] (jelmer) Fix trivial syntax err...
6569: Patch Queue Manager 2012-10-11 [merge] (vila) Clarify how `mergetool` ...

To view the definition of an alias, run bzr alias with the name of the alias as a parameter. For example:

$ bzr alias l5
bzr alias l5="log --limit 5 --line"

To see all your currently defined aliases, run bzr alias without any parameters. For example:

$ bzr alias
bzr alias l="log --line -l10 -n0"
bzr alias l5="log --limit 5 --line"
bzr alias ll="log --line -l10"
bzr alias s="status"

To remove an alias, use the --remove flag:

$ bzr alias --remove ll

Aliases are stored in the [ALIASES] section in the user configuration file ~/.bazaar/bazaar.conf:

[ALIASES]
l = log --line -l10 -n0
s = status
l5 = log --limit 5 --line

You can either use the bzr alias command or edit the configuration directly; the end result will be the same.

You can even override a standard Bazaar command with an alias if you prefer:

$ bzr alias log='log --short'

This example effectively overrides the default output format of bzr log, using the short format instead of the default long format.

To temporarily disable an alias, for example, to fall back on the default Bazaar command, you can use the --no-aliases flag.