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I<Warning>: this role is part of the Rakudo implementation, and is not
a part of the language specification.


L<Metamodel|/language/mop> role for (optionally) versioning metaobjects.


When you declare a type, you can pass it a version, author, and/or API and get
them, like so:


code

=begin code
class Versioned:ver<0.0.1>:auth<github:Kaiepi>:api<1> { }

say Versioned.^ver;  # OUTPUT: «v0.0.1␤»
say Versioned.^auth; # OUTPUT: «github:Kaiepi␤»
say Versioned.^api;  # OUTPUT: «1␤»
=end code


This is roughly equivalent to the following, which also sets them explicitly:


=begin code
BEGIN {
    class Versioned { }
    Versioned.^set_ver:  v0.0.1;
    Versioned.^set_auth: 'github:Kaiepi';
    Versioned.^set_api:  <1>;
}

say Versioned.^ver;  # OUTPUT: «v0.0.1␤»
say Versioned.^auth; # OUTPUT: «github:Kaiepi␤»
say Versioned.^api;  # OUTPUT: «1␤»
=end code


head

Returns the version of the metaobject, if any, otherwise returns L<C<Mu>|/type/Mu>.


Returns the author of the metaobject, if any, otherwise returns an empty string.


Returns the API of the metaobject, if any, otherwise returns an empty string.


root

Metaobject that can hold attributes


role Metamodel::AttributeContainer


Metaobject that supports the C3 method resolution order


role Metamodel::C3MRO


Metarole for documenting types.


role Metamodel::Documenting


Metaobject supporting object finalization


role Metamodel::Finalization


Metaobject that supports storing and introspecting methods


role Metamodel::MethodContainer


Metaobject for generating mixins


role Metamodel::Mixins


Metaobject that supports resolving inherited methods


role Metamodel::MROBasedMethodDispatch


Metaobject that supports multiple inheritance


role Metamodel::MultipleInheritance


Metaobject that supports named types


role Metamodel::Naming


Represents a group of roles with different parameterizations


role Metamodel::ParametricRoleGroupHOW


Represents a non-instantiated, parameterized, role.


role Metamodel::ParametricRoleHOW


Metaobject that supports private methods


role Metamodel::PrivateMethodContainer


Metaobject that supports holding/containing roles


role Metamodel::RoleContainer


Metaobject that supports punning of roles.


role Metamodel::RolePunning


Metarole for type stashes


role Metamodel::Stashing


Metaobject that supports trust relations between types


role Metamodel::Trusting


Metaobjects that support versioning


para

L<Examples| file:../examples/index.podlite>


L<Download |file:../download/index.podlite>


React

=begin React :component<HeaderCol> :id<menu> 
=para L<Documentation|/doc/introduction>
=para L<Modules| /mods>
=para L<Examples| file:../examples/index.podlite>
=para L<Download |file:../download/index.podlite>
=para L<About|file:../about/index.podlite>
=para 🔍 K<⌘K>/K<ctrl-K>
=end React


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role Metamodel::Versioning


A type for methods that behaves in the same way as L<C<Routine>|/type/Routine> with
some exceptions listed below. For details of a method's parameter
list see L<C<Signature>|/type/Signature>.


To create a method outside a L<class definition|/language/typesystem#Methods>,
use the declarators C<my> and C<method>. If an
L<identifier|/language/syntax#Identifiers> is provided the methods name will be
injected into the scope specified by the declarator.


my $m = method ($invocant: $param) {
    say "$invocant: '$param'";
}
"greeting".$m("hello");  # OUTPUT: «greeting: 'hello'␤»


<a b c>.&(my method (List:D:) { say self.raku; self }).say;
# OUTPUT: «("a", "b", "c")␤(a b c)␤»


The invocant of a method defaults to C<self>. A type constraint including a
type-smiley can be used and is honored both for methods defined in a class and
for free floating methods. Call the latter with C<.&> on an object.


my method m(Int:D: $b){
    say self.^name
}
my $i = 1;
$i.&m(<a>);
# OUTPUT: «Int␤»


Please note that the main difference between methods defined within and
without a class is the need to use `&` to invoke them in the latter case. In
case any other sigil is used in the definition, as in the first example, that
sigil can also be used.


X<|Syntax,*%_ (extra named arguments)>
Methods automatically capture extra named arguments into the special variable C<%_>,
where other types of L<C<Routine>|/type/Routine> will throw at runtime. So


Extra arguments will be forwarded by L«C<nextsame> and
friends|/language/functions#Re-dispatching».


class A {
    multi method m(:$a, :$b) { say "2 named" }
}


class B is A {
    method m(:$a) { say "1 named"; nextsame }
}
B.m( :1a, :2b );
# OUTPUT: «1 named␤2 named␤»


Native integer


class int


Dual value number and string


class Allomorph


Thing/object


class Any


Abstract representation of a piece of source code


class AST


Integer (native storage at the platform's atomic operation size)


class atomicint


Code object with its own lexical scope


class Block


Captures the current frame state


class CallFrame


Code object


class Code


Encapsulates instructions about how strings should be sorted


class Collation


Information related to the compiler that is being used


class Compiler


Complex number


class Complex


Dual value complex number and string


class ComplexStr


Object that can be treated as both a string and number


class Cool


Scheduler that synchronously executes code on the current thread


class CurrentThreadScheduler


Calendar date


class Date


Calendar date with time


class DateTime


Distribution::Hash


class Distribution::Hash


Distribution::Locally


class Distribution::Locally


Distribution::Path


class Distribution::Path


Every one of the resources installed with a distribution


class Distribution::Resource


Length of time


class Duration


Management of available encodings


class Encoding::Registry


Rational number (arbitrary-precision)


class FatRat


Rakudo-specific class that wraps around code in other languages (generally NQP)


class ForeignCode


Convert values to a string given a format specification


class Format


Produce Callable for given format specification


class Formatter


An object for performing batches of work in parallel with ordered
output


class HyperSeq


Placeholder for multiple unspecified values/arguments


class HyperWhatever


Specific moment in time


class Instant


Integer (arbitrary-precision)


class Int


Dual value integer and string


class IntStr


Logical superposition of values


class Junction


Tagged location in the source code


class Label


A non-blocking, non-re-entrant, mutual exclusion lock


class Lock::Async


Compile-time routine


class Macro


The root of the Raku type hierarchy.


class Mu


Absence of a value or a benign failure


class Nil


Floating-point number


class Num


Number or object that can act as a number


role Numeric


Dual value floating-point number and string


class NumStr


Unique identification for an object


class ObjAt


Element of a Signature


class Parameter


Perl related information


class Perl


Item container with custom storage and retrieval


class Proxy


Performs batches of work in parallel without respecting original
order.


class RaceSeq


Raku related information


class Raku


Namespace for holding RakuAST related classes


package RakuAST


Contains the information of a RakuDoc block


class RakuAST::Doc::Block


Contains the declarator docs of a RakuAST object


class RakuAST::Doc::Declarator


Contains the information about RakuDoc markup


class RakuAST::Doc::Markup


Contains the information about a RakuDoc paragraph


class RakuAST::Doc::Paragraph


Rational number (limited-precision)


class Rat


Dual value rational number and string


class RatStr


Code object with its own lexical scope and return handling


class Routine


Holds all information needed to unwrap a wrapped routine.


class Routine::WrapHandle


A mostly transparent container used for indirections


class Scalar


Parameter list pattern


class Signature


String of characters


class Str


Contains the result of a string transformation.


class StrDistance


Subroutine


class Sub


Member function that is not inherited by subclasses


class Submethod


Collect performance state for analysis


class Telemetry


Instrument for collecting Thread data


class Telemetry::Instrument::Thread


Instrument for collecting ThreadPoolScheduler data


class Telemetry::Instrument::ThreadPool


Instrument for collecting getrusage data


class Telemetry::Instrument::Usage


Performance data over a period


class Telemetry::Period


Telemetry instrument pod


class Telemetry::Sampler


Unsigned integer (arbitrary-precision)


Subset UInt


Member function


class Method


The Raku Knowledge Base


role Metamodel::Versioning

Methods

method ver

method auth

method api

method set_ver

method set_auth

method set_api

See Also