Method postfix operators

In Chapter 4, Working with Operators, we did not cover the set of special postfix operators, which are related to object-oriented programming. Now it is time to fill that gap. The operators described in this section are the syntactic constructions but they may all be considered postfix operators.

To call a method on an object, the dot operator is used. We have been using it many times in this chapter:

class A {
    method m() {
        return 42;
    }
}

my $o = A.new; # calling the 'new' method
say $o.m();    # calling the 'm' method

If the method does not exist, say, if you call $o.n(), then the call fails:

No such method 'n' for invocant of type 'A'

To prevent the raise of an exception, the .? form of the method call operator can help:

say $o.?m(); # 42
say $o.?n(); # Nil

An existing method is called as usual, while the call of the non-existing method returns Nil and the program continues.

The .+ and .* operators are used to call all the methods with the given name...