Function isArgument

Returns value is
    | { $kind: "GasCoin"; GasCoin: true }
    | { $kind: "Input"; Input: number; type?: "pure" }
    | { $kind: "Input"; Input: number; type?: "object" }
    | { $kind: "Result"; Result: number }
    | { $kind: "NestedResult"; NestedResult: [number, number] }