classProxy {}

A Proxy is an object that allows you to set a hook that executes whenever a value is retrieved from a container (FETCH) or when it is set (STORE). Please note that Proxy can introduce mutability at places where it would break behavior, e.g. in Hash keys.

To create a container that returns twice what was stored in it, you do something like this:

sub double() isrw { my$storage= 0; Proxy.new( FETCH =>method () { $storage* 2 },STORE=>method ($new) { $storage=$new }, ) } my$doubled:= double(); $doubled= 4; say$doubled; # OUTPUT: «8␤» 

Methods§

method new§

methodnew(:&FETCH!,:&STORE! --> Proxy:D)

Creates a new Proxy object. &FETCH is called with one argument (the proxy object) when the value is accessed, and must return the value that the fetch produces. &STORE is called with two arguments (the proxy object, and the new value) when a new value is stored in the container.

Typegraph§