The set of categories, ordered by category-comparator.

A comparator for ASF category keywords, defined as being this ordering:
1. :category-a
2. :category-a-special
3. :category-b
4. :creative-commons
5. :category-x
6. :uncategorised

Returns information on a category as a map with the keys :name and :url (both
strings).  :name is a human-readable name of the category and :url is a link
to the ASF's documentation on the category.

Given an SPDX license expression, returns the overall ASF category of that
expression.  Possible result values are as for license-category.

Returns the lowest (best) category in the given sequence of SPDX license
expressions.

Returns the highest (worst) category for the given sequence of SPDX license
expressions.

Returns the lowest (best) category in the given sequence of categories.

Given an SPDX license identifier, a lice-comb LicenseRef, or 'Public Domain'
(which is not a valid SPDX identifier but is special cased by asf-cat),
returns one of:

nil                 - when license-id is nil, empty or blank
:category-a         - see https://www.apache.org/legal/resolved.html#category-a
:category-a-special - see https://www.apache.org/legal/resolved.html#handling-public-domain-licensed-works
:category-b         - see https://www.apache.org/legal/resolved.html#category-b
:creative-commons   - see https://www.apache.org/legal/resolved.html#cc-by
                      (may be any category - further manual investigation
                      required)
:category-x         - see https://www.apache.org/legal/resolved.html#category-x
:uncategorised      - the ASF category of license-id could not be determined

Note: as of v2.0, expression-category is the preferred primary API for using
asf-cat, since every SPDX license identifier is (by definition) also a valid
SPDX expression.

A comparator for SPDX license identifiers, based on their ASF categories (see
`category-comparator`).

Returns the lowest (best) category in the given sequence of licenses (as per
license-category).

Returns the highest (worst) category for the given sequence of licenses (as
per license-category).

Returns the highest (worst) category for the given sequence of categories.

The URI (as a string) of the Apache Software Foundation's 3rd Party License
Policy