T M
class Method
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Member function

class Method is Routine { }

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

To create a method outside a class definition, use the declarators my and method. If an identifier 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.rakuself }).say;
# OUTPUT: «("a", "b", "c")␤(a b c)␤»

The invocant of a method defaults to 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 .& 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.

Methods automatically capture extra named arguments into the special variable %_, where other types of Routine will throw at runtime. So

method x() {}

is actually equivalent to

method x(*%_{}

Extra arguments will be forwarded by nextsame and friends.

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␤»