perl6/doc/lib/Code

doc src

(title)  Code

    class Code is Any does Callable { ... }

Code is the ultimate base class of all code objects in Perl 6. It exposes functionality that all code objects have. While thunks are directly of type Code , most code objects (such as those resulting from blocks, subroutines or methods) will be of some subclass of Code .

Methods

(head2)  ACCEPTS

    multi method ACCEPTS(Code:D: Mu $topic)

Usually calls the code object and passes $topic as an argument. However, when called on a code object that takes no arguments, the code object is invoked with no arguments and $topic is dropped. The result of the call is returned.

(head2)  arity

    method arity(Code:D:) returns Int:D

Returns the minimum number of positional arguments that must be passed in order to call the code object. Any optional or slurpy parameters in the code object's Signature do not contribute, nor do named parameters.

    sub argless() { }
    sub args($a, $b?) { }
    sub slurpy($a, $b, *@c) { }
    say &argless.arity;             # 0
    say &args.arity;                # 1
    say &slurpy.arity;              # 2

(head2)  count

    method count(Code:D:) returns Real:D

Returns the maximum number of positional arguments that may be passed when calling the code object. For code objects that can accept any number of positional arguments (that is, they have a slurpy parameter), count will return Inf . Named parameters do not contribute.

    sub argless() { }
    sub args($a, $b?) { }
    sub slurpy($a, $b, *@c) { }
    say &argless.count;             # 0
    say &args.count;                # 2
    say &slurpy.count;              # Inf

(head2)  signature

    multi method signature(Code:D:) returns Signature:D

Returns the Signature object for this code object, which describes its parameters.

(head2)  Str

    multi method Str(Code:D:) returns Str:D

Returns the name of the code object.

    sub marine() { }
    say ~&marine;   # marine

perl6/doc/lib/Code

Methods

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