When define a macro, specify the macro parameter type, is it possible?

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1

What i want is like this:

macro macro1(arg : Array(String))
end

macro macro1(arg : Hash(String, String))
end

But, compiler complain the syntax error:

Error: expecting token ')', not ':'

So, i am curious, how to write one macro, which make it support both Array or Hash as args?

Thank you.

2

No, macro parameters can’t have type restrictions. You would have to do it within the macro itself. E.g.

macro test(arg)
  {% if arg.is_a? ArrayLiteral %}
    puts "Array"
  {% elsif arg.is_a? HashLiteral %}
    puts "Hash"
  {% else %}
    puts "Something else"
  {% end %}
end
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