assert that a collection has elements ; that is , it must not be null and must have at least one element.assert.notempty collection , `` collection must have elements '' ; concode_field_sep PlaceHolder placeHolder concode_field_sep void isTrue concode_elem_sep void isTrue concode_elem_sep void isAssignable concode_elem_sep void isAssignable concode_elem_sep void notNull concode_elem_sep void notNull concode_elem_sep void isNull concode_elem_sep void isNull concode_elem_sep void noNullElements concode_elem_sep void noNullElements concode_elem_sep void isInstanceOf concode_elem_sep void isInstanceOf concode_elem_sep void state concode_elem_sep void state