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_docs/basics/operators.md

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+---
+title: Operators
+---
+
+Liquid includes many logical and comparison operators.
+
+### Basic Operators
+
+<table>
+  <tbody>
+    <tr>
+      <td><pre>==</pre></td>
+      <td>equals</td>
+    </tr>
+    <tr>
+      <td><pre>!=</pre></td>
+      <td>does not equal</td>
+    </tr>
+    <tr>
+      <td><pre>&gt;</pre></td>
+      <td>greater than</td>
+    </tr>
+    <tr>
+      <td><pre>&lt;</pre></td>
+      <td>less than</td>
+    </tr>
+    <tr>
+      <td><pre>&gt;=</pre></td>
+      <td>greater than or equal to</td>
+    </tr>
+    <tr>
+      <td><pre>&lt;=</pre></td>
+      <td>less than or equal to</td>
+    </tr>
+    <tr>
+      <td><pre>or</pre></td>
+      <td>logical or</td>
+    </tr>
+    <tr>
+      <td><pre>and</pre></td>
+      <td>logical and</td>
+    </tr>
+  </tbody>
+</table>
+
+For example:
+
+<div>
+{% highlight liquid %}{% raw %}
+{% if product.title == "Awesome Shoes" %}
+  These shoes are awesome!
+{% endif %}
+{% endraw %}{% endhighlight %}
+</div>
+
+You can use multiple operators in a tag:
+
+<div>
+{% highlight liquid %}{% raw %}
+{% if product.type == "Shirt" or product.type == "Shoes" %}
+  This is a shirt or a pair of shoes.
+{% endif %}
+{% endraw %}{% endhighlight %}
+</div>
+
+### contains
+
+`contains` checks for the presence of a substring inside a string.
+
+{% highlight liquid %}{% raw %}
+{% if product.title contains 'Pack' %}
+  This product's title contains the word Pack.
+{% endif %}
+{% endraw %}{% endhighlight %}
+
+`contains` can also check for the presence of a string in an array of strings.
+
+{% highlight liquid %}{% raw %}
+{% if product.tags contains 'Hello' %}
+  This product has been tagged with 'Hello'.
+{% endif %}
+{% endraw %}{% endhighlight %}
+
+`contains` is can only search strings. You cannot use it to check for an object in an array of objects.