Call an object method: Difference between revisions

Content added Content deleted
(→‎{{header|Rust}}: Added info about references to objects.)
(→‎{{header|Perl 6}}: Clean-up and simplification)
Line 1,028: Line 1,028:


=={{header|Perl 6}}==
=={{header|Perl 6}}==
{{works with|Rakudo|2015.12}}
⚫
<lang perl6>class C {
=== Basic method calls ===
⚫
method some-method(){ say 'I haz a method' }
⚫
<lang perl6>class Thing {
⚫
method regular-example() { say 'I haz a method' }

multi method multi-example() { say 'No arguments given' }
multi method multi-example(Str $foo) { say 'String given' }
multi method multi-example(Int $foo) { say 'Integer given' }
};
};
my C $a-c.=new; # we need an instance of C
$a-c.some-method; # so we can call a method


# 'new' is actually a method, not a special keyword:
sub not-a-method(Any:D $obj){ say $obj.WHAT }; # *.WHAT stringifies to the typename in parentheses
my $thing = Thing.new;
$a-c.&not-a-method; # output: '(C)'
my @many-cs = C.new xx 3; # a List of 3 Cs
@many-cs>>.&not-a-method; # let's call not-a-method on all 3 Cs at once
# the >>. hyperoperator is a candidate for autothreading so your order of execution may vary
⚫
my $runtime-method-name = 'some-method';
$a-c."$runtime-method-name"(); # here some very late binding


# No arguments: parentheses are optional
my multi method free-floating-method($self:){ # my is required or the compiler thinks we misplaced a method
$thing.regular-example;
say 'i haz a C' if $self ~~ C # we do the type check by hand
$thing.regular-example();
⚫
};
$thing.multi-example;
$thing.multi-example();


# Arguments: parentheses or colon required
free-floating-method($a-c); # $self is bound to the first parameter
$thing.multi-example("This is a string");
$a-c.&free-floating-method; # dito but automatically
$thing.multi-example: "This is a string";
$thing.multi-example(42);
$thing.multi-example: 42;


# Indirect (reverse order) method call syntax: colon required
$a-c.?does-not-exist; # this method does not exist so it's not called thanks to .?
my $foo = new Thing: ;
multi-example $thing: 42;
</lang>


=== Meta-operators ===
use MONKEY-TYPING;
augment class Int {
method does-not-exists(){} # This is one way to add a method. As usual there are more then one.
}


The <code>.</code> operator can be decorated with meta-operators.
$a-c.?does-not-exists; # now it exists and we can call it


<lang perl6>
my multi method free-floating-method(C:D $self:){} # we could let the compiler do the type check
my @array = <a z c d y>;
my multi method free-floating-method(Int:D $self:){} # or let it pick the right candidate
@array .= sort; # short for @array = @array.sort;
my @a-good-mix = (Int.new((1..100).roll),C.new).roll xx 5; # let's have a mixture of Cs and Ints

@a-good-mix>>.&free-floating-method; # and let Perl 6 pick the right candidate for us
say @array».uc; # uppercase all the strings: A C D Y Z
</lang>

=== Anonymous methods ===

An anonymous method can be called by using the <code>&</code> sigil explicitly.

<lang perl6>
my $object = "a string"; # Everything is an object.
⚫
my method example-method {
return "This is { self }.";
⚫
}


say $object.&example-method; # Outputs "This is a string."
C.some-method(); # actually we don't really need an instance of C. We can call class methods aswell.</lang>
</lang>
Note that, unlike in Perl 5, class names are type objects, not strings. (Type objects are typed variants of the undefined value in Perl 6.)


=={{header|PHP}}==
=={{header|PHP}}==
Retrieved from "https://rosettacode.org/wiki/Call_an_object_method"