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Define a routine that can be called using method syntax

sqrt can be called via function syntax:

 > sqrt 16 4

It can also be called via method syntax:

 > 16.sqrt 4

Is there a way to make custom routines invokable through method syntax?

For example, define sq :

 > sub sq(Int $n) { $n*$n } sub sq (Int $n) { #`(Sub|64042864) ... } > sq 4 16

Is there a way to make it callable as a method? I.e.

 > 4.sq
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Is there a way to make custom routines invokable through method syntax?

Yes, just use the syntax .& , As in:

 625.&sqrt.say # 25

Invocant is passed as the first argument:

 sub sq { $^a² }; say 4.&sq 4.&sq.say # 16

The only catch is that you need to use unspace if you want to break the chain of methods into these few lines:

 4.&sq\ .&sq.say;
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You can use the monkey to enter text Int . Expect that the optimizer is a guarantee, your will / boobs are compressed, and the world ends in general. The skill of the monkey is evil. Do not use it if you do not need to.

 use MONKEY-TYPING; augment class Int { method sq(Int:D $i:){ $i * $i } }; my Int $i = 4; say $i.sq;

You can mix a role with an object. Note that the object is an object, not an Int class and a $i container.

 my $i = 4 but role :: { method sq(Int:D $i:){ $i * $i } }; say $i.sq;

You can create a free floating method and use the method call operator .& .

 my method sq(Int:D $i:){ $i * $i }; my $i = 4; say $i.&sq;

EDIT:

If you really want to break assumptions, you can even access private attributes.

 class Foo { has $!bar = 'meow'; }; use MONKEY-TYPING; augment class Foo { method baz { say $!bar } }; Foo.new.baz # OUTPUT«meow␤»
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