<p>
The built-in function <code>clear</code> takes an argument of <a href="#Map_types">map</a>,
<a href="#Slice_types">slice</a>, or <a href="#Type_parameter_declarations">type parameter</a> type,
and deletes or zeroes out all elements
[<a href="#Go_1.21">Go 1.21</a>].
</p>

<pre class="grammar">
Call        Argument type     Result

clear(m)    map[K]T           deletes all entries, resulting in an

for strings, and <code>nil</code> for pointers, functions, interfaces, slices, channels, and maps.
This initialization is done recursively, so for instance each element of an
array of structs will have its fields zeroed if no value is specified.
</p>
<p>
These two simple declarations are equivalent:
</p>

<pre>
var i int
var i int = 0
</pre>

<p>
After
</p>

<pre>