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use v6-perlito;

class Main {
    say '1..4';
    my $a = sub () { 3 };
    say 'ok 1 - create function';
    if $a.() != 3 {
        print 'not '
    }
    say 'ok 2 - apply';
    $a = ( sub () { 4 } ).();
    if $a != 4 {
        print 'not '
    }
    say 'ok 3 - apply in line';
    $a = ( sub () { sub () { 5 } } ).();
    if $a.() != 5 {
        print 'not '
    }
    say 'ok 4 - return function';
}