| expect_that(x, is_true()) | 
expect_true(x) | 
| expect_that(x, is_false()) | 
expect_false(x) | 
| expect_that(x, is_a(y)) | 
expect_is(x, y) | 
| expect_that(x, equals(y)) | 
expect_equal(x, y) | 
| expect_that(x, is_equivalent_to(y)) | 
expect_equivalent(x, y) | 
| expect_that(x, is_identical_to(y)) | 
expect_identical(x, y) | 
| expect_that(x, matches(y)) | 
expect_matches(x, y) | 
| expect_that(x, prints_text(y)) | 
expect_output(x, y) | 
| expect_that(x, shows_message(y)) | 
expect_message(x, y) | 
| expect_that(x, gives_warning(y)) | 
expect_warning(x, y) | 
| expect_that(x, throws_error(y)) | 
expect_error(x, y) |