@Test
void typeVariable() {

    assertThat(Literal.variable(String.class)).isEqualTo("java.lang.String.class");
    assertThat(Literal.variable(Types.list(String.class))).isEqualTo("core.framework.util.Types.list(java.lang.String.class)");
    assertThat(Literal.variable(Types.optional(String.class))).isEqualTo("core.framework.util.Types.optional(java.lang.String.class)");
}