Bucket Plugin
==============

The ``bucket`` plugin helps you keep a balanced files tree for your library
by gathering your files into buckets folders representing ranges.
This kind of files organization is usually used to classify your music by
periods (eg *1960s*, *1970s* etc), or to divide bloated folders into smaller
subfolders by grouping albums/artist alphabetically (eg *A-F*, *G-M*, *N-Z*).
To use plugin, enable it by including `bucket` into `plugins` line of your
beets config. The plugin provides a template function called `%bucket` for
use in path format expressions::

    paths:
        default: /%bucket($year)/%bucket($artist)/$albumartist-$album-$year

You must then define what ranges representations you allow in the `bucket:`
section in the config file :

    bucket:
        bucket_alpha: ['A-F', 'G-M', 'N-Z']
        bucket_year:  ['1980s', '1990s', '2000s']

The `bucket_year` parameter is used for all substitutions occuring on the
`$year` field, while `bucket_alpha` takes care of the others textual fields.

The definition of a range is somewhat loose, and multiple formats are allowed :

- for alpha ranges: the range is defined by the lowest and highest (ascii-wise)
alphanumeric characters. eg *'ABCD'*, *'A-D'*, *'A->D'*, *[AD]* are equivalent.
- for year ranges: digits characters are extracted, and in case of doubt XXth
century is assumed. eg *'1975-77'*, *'1975,76,77'* and *'1975-1977'* are
 equivalent. If no upper bound is given, the range is extended to current year (unless a
later range is defined). eg *'1975'* encompasses all years from 1975 until now.