In Python, Python has Union type, which is convenient when a method can accept multi types:
from typing import Union
def test(x: Union[str,int,float,]):
print(x)
if __name__ == '__main__':
test(1)
test('str')
test(3.1415926)
Raku probably doesn't have Union type as Python, but a where clause can achieve a similar effect:
sub test(\x where * ~~ Int | Str | Rat) {
say(x)
}
sub MAIN() {
test(1);
test('str');
test(3.1415926);
}
I wander if Raku have a possibility to provide the Union type as Python?
# vvvvvvvvvvvvvvvvvvvv - the Union type doesn't exist in Raku now.
sub test(Union[Int, Str, Rat] \x) {
say(x)
}
My answer (which is very similar to your first solution ;) would be:
subset Union where Int | Rat | Str;
sub test(Union \x) {
say(x)
}
sub MAIN() {
test(1);
test('str');
test(pi);
}
Constraint type check failed in binding to parameter 'x';
expected Union but got Num (3.141592653589793e0)
(or you can put a where clause in the call signature, as you have it)
In contrast to Python:
So - the raku syntax is there to do what you ask ... sure, it's a different language so it does it in a different way.
Personally I think that a typed language should fail if type checks are breached. It seems to me that type hinting that is not always enforced is a false comfort blanket.
On a wider point, raku also offers built in Allomorph types for IntStr, RatStr, NumStr and ComplexStr - so you can work in a mixed mode using both string and math functions