role Metamodel::Trusting

Metaobject that supports trust relations between types

role Metamodel::Trusting is SuperClass { ... }

Warning: this role is part of the Rakudo implementation, and is not a part of the language specification.

Normally, code in a class or role can only access its own private methods. If another type declares that it trusts that first class, then access to private methods of that second type is possible. Metamodel::Trusting implements that aspect of the Raku object system.

class A {
    my class B {
        trusts A;   # that's where Metamodel::Trusting comes in 
        method !private_method() {
            say "Private method in B";
        }
    }
    method build-and-poke {
        # call a private method from B 
        # disallowed if A doesn't trust B 
        B.new()!B::private_method();
    }
};
 
A.build-and-poke;   # Private method in A

Methods

method add_trustee

method add_trustee($typeMu $trustee)

Trust $trustee.

class A {
    BEGIN A.^add_trustee(B);
    # same as 'trusts B'; 
}

method trusts

method trusts($type --> List)

Returns a list of types that the invocant trusts.

class A { trusts Int};
say .^name for A.^trusts;       # Int

method is_trusted

method is_trusted($type$claimant)

Returns 1 if $type trusts $claimant, and 0 otherwise. Types always trust themselves.

Type Graph

Type relations for 404

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