Fetch a value from the hash. Raise an error if the key does not exist in the hash.
immutable data = ["foo": V(1)]; immutable subject = new immutable(Hash!(string, int))(data); auto result = subject.insert("bar", 2); assert(result["bar"] == 2); assert(result["foo"] == 1);
See Implementation
Fetch a value from the hash. Raise an error if the key does not exist in the hash.