Register an HTML head resource. About is either an atom that
specifies an HTTP location or a term Alias(Sub). This works
similar to absolute_file_name/2. See location_path/2 for
details. Recognised properties are:
- requires(+Requirements)
- Other required script and css files. If this is a plain
file name, it is interpreted relative to the declared
resource. Requirements can be a list, which is equivalent
to multiple requires properties.
- virtual(+Bool)
- If
true
(default false
), do not include About itself,
but only its dependencies. This allows for defining an
alias for one or more resources.
- ordered(+Bool)
- Defines that the list of requirements is ordered, which
means that each requirement in the list depends on its
predecessor.
- aggregate(+List)
- States that About is an aggregate of the resources in
List. This means that if both About and one of the
elements of List appears in the dependencies, About
is kept and the smaller one is dropped. If there are a
number of dependencies on the small members, these are
replaced with dependency on the big (aggregate) one,
for example, to specify that a big javascript is
actually the composition of a number of smaller ones.
- mime_type(-Mime)
- May be specified for non-virtual resources to specify
the mime-type of the resource. By default, the mime
type is derived from the file name using
file_mime_type/2.
Registering the same About multiple times extends the properties
defined for About. In particular, this allows for adding
additional dependencies to a (virtual) resource.