How to specify any/unknown/variant type in GDScript?

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Is there a way to specify an unknown type in GDScript?

GDScript docs use the type Variant for this (for example in Array.count method).

Say, I'd like to write an identity function. I can do it like so:

func identity(x):
    return x

But I'd like to declare that both the parameter type and return value could be anything. Something like:

func identity(x: Variant) -> Variant:
    return x

This doesn't work though. Variant is not a known type name. I tried various names, bot nothing seems to work.

Is the only option to leave off the type?

gdscript godot static-typing
1 Answers

Yes, the only option is to not specify the type.

This function:

func identity(x):
    return x

Takes Variant and returns Variant.

There is a Variant class defined in Godot in C++. Which, as you have found out, we cannot use it by name in GDScript.

Please notice that the docs use a notation based on C++. For instance int count (Variant value) does not only differ from GDScript because of Variant, but also in that you specify the type after the parameters not before the name, also you use func.

This is how int count (Variant value) looks in GDScript: func count(value) -> int:, and this is the C++ definition: int Array::count(const Variant &p_value) const (source). Compare the C++ definition with the one on the documentation.

For another example, this is how Array duplicate (bool deep=false) looks like in GDSCript: func duplicate(deep:bool=false) -> Array:, and this is the C++ definition: Array Array::duplicate(bool p_deep) const. (source). Notice the C++ definition does not indicate the parameter will be optional, that information is added for the script binding.

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