Prototype subroutines
12345678910111213141516171819202122232425262728293031323334353637383940414243
use v6;
# wat prototype. the {*} marks where child subroutines fill in the blank
# $*yes is a dynamic variable (i.e. it doesn't have to be declared in the child subroutines to be used)
proto sub wat($first, $second, |) {
my $*yes = "$first $second";
{*}
}
# dispatch here when 3rd argument Int
multi sub wat($a, $b, Int $third) {
join ' ', $*yes xx $third
}
# dispatch here when 3rd argument Str
multi sub wat($a, $b, Str $third) {
"$*yes $third"
}
my @int-dispatch-args = 'foo', 'bar', 4; # triggers Int dispatch
my @str-dispatch-args = 'finger', 'food', 'fad'; # triggers Str dispatch
say "wat(Int dispatch with prototype): ", wat |@int-dispatch-args;
say "wat(Str dispatch with prototype): ", wat |@str-dispatch-args;
# helper method style. this will be used by the Int and Str woot dispatches
multi sub woot($first, $second) {
"$first $second"
}
# Int dispatch using helper subroutine
multi sub woot($first, $second, Int $third) {
join ' ', woot($first, $second) xx $third
}
# Str dispatch using helper subroutine
multi sub woot($first, $second, Str $third) {
"&woot($first, $second) $third"
}
say 'woot(Int dispatch no prototype): ', woot |@int-dispatch-args;
say 'woot(Str dispatch no prototype): ', woot |@str-dispatch-args;
Raku
INFO