import * as err from "@thi.ng/errors";

err.illegalArity(3)
// Error: illegal arity: 3

err.illegalArgs("expected foo");
// Error: illegal argument(s): expected foo

err.illegalState("oops");
// Error: illegal state: oops

err.unsupported("TODO not yet implemented")
// Error: unsupported operation: TODO not yet implemented

// define custom error
const MyError = err.defError(
    () => "Eeek... ",
    (x) => x + " is not allowed!"
);

try {
    throw new MyError(23);
} catch(e) {
    console.warn(e.message);
    console.log(e instanceof Error);
}
// Eeek... 23 is not allowed!
// true