Kaya 0.4.4 reference for Builtins::Getting_Tag_From_Non_Union

Builtins::Getting_Tag_From_Non_Union()

Usage

This Exception is thrown when a case statement is used on something other than an ADT, for example:

i = 5;
case i of {
    A(a) -> putStrLn(a);
    | B(b) -> putStrLn(b);
}

In the example, the compiler would catch the error - in practice this error can occur when accessing an uninitialised value, or a value with inconsistent type information due to foreign function calls.