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<h1 class="refname">Ds\Map::put</h1>
<p class="verinfo">(PECL ds >= 1.0.0)</p><p class="refpurpose"><span class="refname">Ds\Map::put</span> — <span class="dc-title">Associates a key with a value</span></p>
</div>
<div class="refsect1 description" id="refsect1-ds-map.put-description">
<h3 class="title">Description</h3>
<div class="methodsynopsis dc-description">
<span class="modifier">public</span> <span class="type"><span class="type void">void</span></span> <span class="methodname"><strong>Ds\Map::put</strong></span>
( <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <code class="parameter">$key</code></span>
, <span class="methodparam"><span class="type"><a href="language.pseudo-types.html#language.types.mixed" class="type mixed">mixed</a></span> <code class="parameter">$value</code></span>
)</div>
<p class="para rdfs-comment">
Associates a <code class="parameter">key</code> with a <code class="parameter">value</code>,
overwriting a previous association if one exists.
</p>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
Keys of type <span class="type"><a href="language.types.object.html" class="type object">object</a></span> are supported.
If an object implements <strong class="classname">Ds\Hashable</strong>,
equality will be determined by the object's <code class="code">equals</code> function.
If an object does not implement <strong class="classname">Ds\Hashable</strong>,
objects must be references to the same instance to be considered equal.
</p>
</p></blockquote>
<blockquote class="note"><p><strong class="note">Note</strong>:
<p class="para">
You can also use array syntax to associate values by key, eg. <code class="code">$map["key"] = $value</code>.
</p>
</p></blockquote>
<div class="caution"><strong class="caution">Caution</strong>
<p class="para">
Be careful when using array syntax. Scalar keys will be coerced to
integers by the engine. For example, <code class="code">$map["1"]</code> will attempt
to access <code class="code">int(1)</code>, while <code class="code">$map->get("1")</code> will
correctly look up the string key.
</p>
<p class="para">
See <a href="language.types.array.html" class="link">Arrays</a>.
</p>
</div>
</div>
<div class="refsect1 parameters" id="refsect1-ds-map.put-parameters">
<h3 class="title">Parameters</h3>
<dl>
<dt>
<code class="parameter">key</code></dt>
<dd>
<p class="para">
The key to associate the value with.
</p>
</dd>
<dt>
<code class="parameter">value</code></dt>
<dd>
<p class="para">
The value to be associated with the key.
</p>
</dd>
</dl>
</div>
<div class="refsect1 returnvalues" id="refsect1-ds-map.put-returnvalues">
<h3 class="title">Return Values</h3>
<p class="para">
No value is returned.
</p>
</div>
<div class="refsect1 examples" id="refsect1-ds-map.put-examples">
<h3 class="title">Examples</h3>
<div class="example" id="example-5274">
<p><strong>Example #1 <span class="function"><strong>Ds\Map::put()</strong></span> example</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br />$map </span><span style="color: #007700">= new \</span><span style="color: #0000BB">Ds</span><span style="color: #007700">\</span><span style="color: #0000BB">Map</span><span style="color: #007700">();<br /><br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(</span><span style="color: #DD0000">"a"</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(</span><span style="color: #DD0000">"b"</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(</span><span style="color: #DD0000">"c"</span><span style="color: #007700">, </span><span style="color: #0000BB">3</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">print_r</span><span style="color: #007700">(</span><span style="color: #0000BB">$map</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output
something similar to:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
Ds\Map Object
(
[0] => Ds\Pair Object
(
[key] => a
[value] => 1
)
[1] => Ds\Pair Object
(
[key] => b
[value] => 2
)
[2] => Ds\Pair Object
(
[key] => c
[value] => 3
)
)
</pre></div>
</div>
</div>
<div class="example" id="example-5275">
<p><strong>Example #2 <span class="function"><strong>Ds\Map::put()</strong></span> example using objects as keys</strong></p>
<div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB"><?php<br /></span><span style="color: #007700">class </span><span style="color: #0000BB">HashableObject </span><span style="color: #007700">implements \</span><span style="color: #0000BB">Ds</span><span style="color: #007700">\</span><span style="color: #0000BB">Hashable<br /></span><span style="color: #007700">{<br /> </span><span style="color: #FF8000">/**<br /> * An arbitrary value to use as the hash value. Does not define equality.<br /> */<br /> </span><span style="color: #007700">private </span><span style="color: #0000BB">$value</span><span style="color: #007700">;<br /><br /> public function </span><span style="color: #0000BB">__construct</span><span style="color: #007700">(</span><span style="color: #0000BB">$value</span><span style="color: #007700">)<br /> {<br /> </span><span style="color: #0000BB">$this</span><span style="color: #007700">-></span><span style="color: #0000BB">value </span><span style="color: #007700">= </span><span style="color: #0000BB">$value</span><span style="color: #007700">;<br /> }<br /><br /> public function </span><span style="color: #0000BB">hash</span><span style="color: #007700">()<br /> {<br /> return </span><span style="color: #0000BB">$this</span><span style="color: #007700">-></span><span style="color: #0000BB">value</span><span style="color: #007700">;<br /> }<br /><br /> public function </span><span style="color: #0000BB">equals</span><span style="color: #007700">(</span><span style="color: #0000BB">$obj</span><span style="color: #007700">): </span><span style="color: #0000BB">bool<br /> </span><span style="color: #007700">{<br /> return </span><span style="color: #0000BB">$this</span><span style="color: #007700">-></span><span style="color: #0000BB">value </span><span style="color: #007700">=== </span><span style="color: #0000BB">$obj</span><span style="color: #007700">-></span><span style="color: #0000BB">value</span><span style="color: #007700">;<br /> }<br />}<br /><br /></span><span style="color: #0000BB">$map </span><span style="color: #007700">= new \</span><span style="color: #0000BB">Ds</span><span style="color: #007700">\</span><span style="color: #0000BB">Map</span><span style="color: #007700">();<br /><br /></span><span style="color: #0000BB">$obj </span><span style="color: #007700">= new \</span><span style="color: #0000BB">ArrayIterator</span><span style="color: #007700">([]);<br /><br /></span><span style="color: #FF8000">// Using the same instance multiple times will overwrite the previous value.<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(</span><span style="color: #0000BB">$obj</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(</span><span style="color: #0000BB">$obj</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Using multiple instances of the same object will create new associations.<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(new \</span><span style="color: #0000BB">stdClass</span><span style="color: #007700">(), </span><span style="color: #0000BB">3</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(new \</span><span style="color: #0000BB">stdClass</span><span style="color: #007700">(), </span><span style="color: #0000BB">4</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Using multiple instances of equal hashable objects will overwrite previous values.<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(new \</span><span style="color: #0000BB">HashableObject</span><span style="color: #007700">(</span><span style="color: #0000BB">1</span><span style="color: #007700">), </span><span style="color: #0000BB">5</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(new \</span><span style="color: #0000BB">HashableObject</span><span style="color: #007700">(</span><span style="color: #0000BB">1</span><span style="color: #007700">), </span><span style="color: #0000BB">6</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(new \</span><span style="color: #0000BB">HashableObject</span><span style="color: #007700">(</span><span style="color: #0000BB">2</span><span style="color: #007700">), </span><span style="color: #0000BB">7</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$map</span><span style="color: #007700">-></span><span style="color: #0000BB">put</span><span style="color: #007700">(new \</span><span style="color: #0000BB">HashableObject</span><span style="color: #007700">(</span><span style="color: #0000BB">2</span><span style="color: #007700">), </span><span style="color: #0000BB">8</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$map</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?></span>
</span>
</code></div>
</div>
<div class="example-contents"><p>The above example will output
something similar to:</p></div>
<div class="example-contents screen">
<div class="cdata"><pre>
object(Ds\Map)#1 (5) {
[0]=>
object(Ds\Pair)#7 (2) {
["key"]=>
object(ArrayIterator)#2 (1) {
["storage":"ArrayIterator":private]=>
array(0) {
}
}
["value"]=>
int(2)
}
[1]=>
object(Ds\Pair)#8 (2) {
["key"]=>
object(stdClass)#3 (0) {
}
["value"]=>
int(3)
}
[2]=>
object(Ds\Pair)#9 (2) {
["key"]=>
object(stdClass)#4 (0) {
}
["value"]=>
int(4)
}
[3]=>
object(Ds\Pair)#10 (2) {
["key"]=>
object(HashableObject)#5 (1) {
["value":"HashableObject":private]=>
int(1)
}
["value"]=>
int(6)
}
[4]=>
object(Ds\Pair)#11 (2) {
["key"]=>
object(HashableObject)#6 (1) {
["value":"HashableObject":private]=>
int(2)
}
["value"]=>
int(8)
}
}
</pre></div>
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