proc resume*(self: GDFunctionState; arg: Variant = newVariant()): Variant {.gcsafe, locks: 0.}
proc isValid*(self: GDFunctionState; extendedCheck: bool = false): bool {.gcsafe, locks: 0.}
method signalCallback*(self: GDFunctionState; variantArgs: varargs[Variant]) {. gcsafe, locks: 0, base.}