presto-main/src/main/java/io/prestosql/operator/scalar/MapSubscriptOperator.java/MapSubscriptOperator/create
class MapSubscriptOperator:        public PrestoException create(ConnectorSession session, Object value)
        {
            if (castFunction != null) {
                try {
                    Slice varcharValue = (Slice) functionInvoker.invoke(castFunction, session, value);
                    return new PrestoException(INVALID_FUNCTION_ARGUMENT, format("Key not present in map: %s", varcharValue.toStringUtf8()));
                }
                catch (RuntimeException ignored) {
                }
            }
            return new PrestoException(INVALID_FUNCTION_ARGUMENT, "Key not present in map");
        }