ignore (ANSI and GNU Common Lisp Document)

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#### 3.8.19 ignore, ignorable [Declaration]

#### Syntax::

`(ignore {var | (function fn)}*)`

`(ignorable {var | (function fn)}*)`

#### Arguments::

var—a variable name.

fn—a function name.

#### Valid Context::

declaration

#### Binding Types Affected::

variable, function

#### Description::

The ignore and ignorable declarations refer to for-value references to variable bindings for the vars and to function bindings for the fns.

An ignore declaration specifies that for-value references to the indicated bindings will not occur within the scope of the declaration. Within the scope of such a declaration, it is desirable for a compiler to issue a warning about the presence of either a for-value reference to any var or fn, or a special declaration for any var.

An ignorable declaration specifies that for-value references to the indicated bindings might or might not occur within the scope of the declaration. Within the scope of such a declaration, it is not desirable for a compiler to issue a warning about the presence or absence of either a for-value reference to any var or fn, or a special declaration for any var.

When not within the scope of a ignore or ignorable declaration, it is desirable for a compiler to issue a warning about any var for which there is neither a for-value reference nor a special declaration, or about any fn for which there is no for-value reference.

Any warning about a “used” or “unused” binding must be of type style-warning, and may not affect program semantics.

The stream variables established by with-open-file, with-open-stream, with-input-from-string, and with-output-to-string, and all iteration variables are, by definition, always “used”. Using `(declare (ignore v))`, for such a variable v has unspecified consequences.

#### See Also::

declare

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