Hello venerable monks,

I have been playing around with rakudo and have a few questions demonstrated in the following piece of code:

multi sub to_num(Str $number where { $_ ~~ /^ \d+ $/ }) returns Num { 
++$number }
my $s = "10";
my $i = to_num($s);
say 'before: ' ~ $s.WHAT; # before: Str
say 'after : ' ~ $i.WHAT; # after : Num

[download]

Questions:

Casting

Is it currently possible to convert a type Str "10" to a type Num 10 e.g. the return value of the builtin prompt()?

Return types

Should a sub/method/function complain if the return value does not match the specified type, in this case Num?

Signatures

Is the return type part of the signature and if not should it be?

Thanks =)

Smoothie, smoothie, hundre prosent naturlig!

In reply to casting, signatures and return types in perl 6 (rakudo) by j1n3l0

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