class Metamodel::PackageHOW
  does Metamodel::Naming
  does Metamodel::Documenting
  does Metamodel::Stashing
  does Metamodel::TypePretense
  does Metamodel::MethodDelegation { }

Warning: this class is part of the Rakudo implementation, and is not a part of the language specification.

Metamodel::PackageHOW is the metaclass behind the package keyword.

package P {};
say P.HOW; # OUTPUT: «Perl6::Metamodel::PackageHOW.new␤»

Methods

method archetypes

Defined as:

method archetypes()

Returns the archetypes for this model, that is, the properties a metatype can implement.

method new

Defined as:

method new(*%named)

Creates a new PackageHOW.

method new_type

Defined as:

method new_type(:$name = '<anon>', :$repr, :$ver, :$auth)

Creates a new package, with optional representation, version and auth field.

compose

Defined as:

method compose($obj, :$compiler_services)

Sets the metapackage as composed.

is_composed

Defined as:

method is_composed($obj)

Returns the composed status of the metapackage.

Type Graph

Routines supplied by role Metamodel::Naming

Metamodel::PackageHOW does role Metamodel::Naming, which provides the following routines:

(Metamodel::Naming) method name

method name($type)

Returns the name of the metaobject, if any.

say 42.^name;       # OUTPUT: «Int␤»

(Metamodel::Naming) method set_name

method set_name($type, $new_name)

Sets the new name of the metaobject.

Routines supplied by role Metamodel::Documenting

Metamodel::PackageHOW does role Metamodel::Documenting, which provides the following routines:

(Metamodel::Documenting) method set_why

method set_why($why)

Sets the documentation for a type to $why.

(Metamodel::Documenting) method WHY

method WHY()

Returns the documentation for a type.

Routines supplied by role Metamodel::Stashing

Metamodel::PackageHOW does role Metamodel::Stashing, which provides the following routines:

(Metamodel::Stashing) method add_stash

method add_stash($type_obj)

Creates and sets a stash for a type, returning $type_obj.

This method is typically called as the last step of creating a new type. For example, this is how it would be used in a minimal HOW that only supports naming and stashing:

class WithStashHOW
    does Metamodel::Naming
    does Metamodel::Stashing
{
    method new_type(WithStashHOW:_: Str:D :$name! --> Mu) {
        my WithStashHOW:D $meta := self.new;
        my Mu             $type := Metamodel::Primitives.create_type: $meta, 'Uninstantiable';
        $meta.set_name: $type, $name;
        self.add_stash: $type
    }
}

my Mu constant WithStash = WithStashHOW.new_type: :name<WithStash>;
say WithStash.WHO; # OUTPUT: «WithStash␤»