#### 24.2.4 with-compilation-unit [Macro]

`with-compilation-unit` ([[!option]]) {form}* ⇒ {result}*

option ::=`:override` override

#### Arguments and Values::

override—a generalized boolean; evaluated. The default is nil.

forms—an implicit progn.

results—the values returned by the forms.

#### Description::

Executes forms from left to right. Within the dynamic environment of with-compilation-unit, actions deferred by the compiler until the end of compilation will be deferred until the end of the outermost call to with-compilation-unit.

The set of options permitted may be extended by the implementation, but the only standardized keyword is `:override`.

If nested dynamically only the outer call to with-compilation-unit has any effect unless the value associated with `:override` is true, in which case warnings are deferred only to the end of the innermost call for which override is true.

The function compile-file provides the effect of

     (with-compilation-unit (:override nil) ...)

around its code.

Any implementation-dependent extensions can only be provided as the result of an explicit programmer request by use of an implementation-dependent keyword. Implementations are forbidden from attaching additional meaning to a use of this macro which involves either no keywords or just the keyword `:override`.

#### Examples::

If an implementation would normally defer certain kinds of warnings, such as warnings about undefined functions, to the end of a compilation unit (such as a file), the following example shows how to cause those warnings to be deferred to the end of the compilation of several files.

     (defun compile-files (&rest files)
       (with-compilation-unit ()
         (mapcar #'(lambda (file) (compile-file file)) files)))

     (compile-files "A" "B" "C")

Note however that if the implementation does not normally defer any warnings, use of with-compilation-unit might not have any effect.

#### See Also::

compile , compile-file