# ASSERT proc

Source: https://ref.dm-lang.org/proc/ASSERT

### Format
> `ASSERT(expression)`

### Args
> expression: an expression which should always be true

This is used to make a sanity check. If the given expression is false, the current procedure crashes, generating diagnostic debugging output, which includes the expression, a stack dump, and so forth.

### See also
- [CRASH proc](https://ref.dm-lang.org/proc/CRASH.md)
- [DEBUG definition](https://ref.dm-lang.org/DM/preprocessor/define/DEBUG.md)
- [stddef.dm file](https://ref.dm-lang.org/appendix/stddefdotdm.md)