# destack:assert

`import destack:assert`

## Structs

- [AssertionError](/docs/language/standard-library/modules/assert/struct/assertion-error/) — Failed assertion details.

## Type aliases

- [Details](/docs/language/standard-library/modules/assert/type-alias/details/) — Structured details attached to one assertion event.

## Functions

- [always](/docs/language/standard-library/modules/assert/function/always/) — Record that condition should always hold when reached.
- [assert](/docs/language/standard-library/modules/assert/function/assert/) — Assert that condition is true.
- [contains](/docs/language/standard-library/modules/assert/function/contains/) — Assert that values contains expected.
- [deepEqual](/docs/language/standard-library/modules/assert/function/deep-equal/) — Assert that actual deeply equals expected.
- [equal](/docs/language/standard-library/modules/assert/function/equal/) — Assert that actual equals expected.
- [fail](/docs/language/standard-library/modules/assert/function/fail/) — Fail unconditionally.
- [notContains](/docs/language/standard-library/modules/assert/function/not-contains/) — Assert that values does not contain expected.
- [notDeepEqual](/docs/language/standard-library/modules/assert/function/not-deep-equal/) — Assert that actual does not deeply equal expected.
- [notEqual](/docs/language/standard-library/modules/assert/function/not-equal/) — Assert that actual does not equal expected.
- [notSame](/docs/language/standard-library/modules/assert/function/not-same/) — Assert that actual is not the same value as expected.
- [ok](/docs/language/standard-library/modules/assert/function/ok/) — Assert that condition is true.
- [reachable](/docs/language/standard-library/modules/assert/function/reachable/) — Record that a named code path was reached.
- [same](/docs/language/standard-library/modules/assert/function/same/) — Assert that actual is the same value as expected.
- [sometimes](/docs/language/standard-library/modules/assert/function/sometimes/) — Record that condition should become true in some explored run.
- [unreachable](/docs/language/standard-library/modules/assert/function/unreachable/) — Mark this code path as unreachable.