## Macro: COMMON-LISP:ASSERT
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> Signals an error if the value of TEST-FORM is NIL. Returns NIL.
> 
> Optional DATUM and ARGUMENTS can be used to change the signaled
> error condition and are interpreted as in (APPLY #'ERROR DATUM
> ARGUMENTS).
> 
> Continuing from the signaled error using the CONTINUE restart will
> allow the user to alter the values of the SETFable locations
> specified in PLACES and then start over with TEST-FORM.
> 
> If TEST-FORM is of the form
> 
> (FUNCTION ARG*)
> 
> where FUNCTION is a function (but not a special operator like
> CL:OR, CL:AND, etc.) the results of evaluating the ARGs will be
> included in the error report if the assertion fails.

### Lambda list
```cl
(sb-impl::test-form &optional sb-impl::places sb-impl::datum &rest sb-impl::arguments)
```