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documentation/basics/true-and-false.md

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+---
+layout: default
+title: Truthy and Falsy
+nav:
+  group: Liquid Variables
+  weight: 6
+---
+
+# Truthy and Falsy in Liquid
+
+
+
+In programming, we describe “truthy” and “falsy” as anything that returns true or  false, respectively, when used inside an if statement.
+
+## What is truthy? 
+
+All values in Liquid are truthy, with the exception of <tt>nil</tt> and <tt>false</tt>. 
+
+In the example below, the text “Tobi” is not a boolean, but it is truthy in a conditional:
+
+{% highlight html %}{% raw %}
+{% assign tobi = 'Tobi' %}
+{% if tobi %}
+This will always be true.
+{% endif %}
+{% endraw %}{% endhighlight %}
+
+[Strings](/themes/liquid-documentation/basics/types/#strings), even when empty, are truthy. The example below will result in empty HTML tags if <code>settings.fp_heading</code> is empty: 
+
+<p class="input">Input</p>
+{% highlight html %}{% raw %}
+{% if settings.fp_heading %}
+<h1>{{ settings.fp_heading }}</h1>
+{% endif %}
+{% endraw %}{% endhighlight %}
+
+
+<p class="output">Output</p>
+{% highlight html %}{% raw %}
+<h1></h1>
+{% endraw %}{% endhighlight %}
+
+To avoid this, you can check to see if the string is <code>blank</code>, as follows: 
+
+<div>
+{% highlight html %}{% raw %}
+{% unless settings.fp_heading == blank %}
+	<h1>{{ settings.fp_heading }}</h1>
+{% endunless %}
+{% endraw %}{% endhighlight %}
+</div>
+
+<hr/>
+
+An [EmptyDrop](/themes/liquid-documentation/basics/types/#empty-drop) is also truthy. In the example below, if <code>settings.page</code> is an empty string or set to a hidden or deleted object, you will end up with an EmptyDrop. The result is an undesirable empty &lt;div&gt;:
+
+<p class="input">Input</p>
+{% highlight html %}{% raw %}
+{% if pages[settings.page] %}
+<div>{{ pages[settings.page].content }}</div>
+{% endif %}
+{% endraw %}{% endhighlight %}
+
+
+<p class="output">Output</p>
+{% highlight html %}{% raw %}
+<div></div>
+{% endraw %}{% endhighlight %}
+
+
+## What is falsy?
+
+The only values that are falsy in Liquid are <tt>nil</tt> and <tt>false</tt>.
+
+[nil](/themes/liquid-documentation/basics/types/#nil) is returned when a Liquid object doesn't have anything to return. For example, if a collection doesn't have a collection image, collection.image will be set to <tt>nil</tt>. Since that is “falsy”, you can do this:
+
+{% highlight html %}{% raw %}
+{% if collection.image %}
+<!-- output collection image -->
+{% endif %}
+{% endraw %}{% endhighlight %}
+
+The value <tt>false</tt> is returned through many Liquid object properties such as <tt>product.available</tt>.
+
+## Summary
+
+The table below summarizes what is truthy or falsy in Liquid. 
+
+|               | truthy        | falsy         |
+| ------------- |:-------------:|:-------------:|
+| true          | &times; |  |
+| false         |       | &times; |
+| nil          |  | &times; |
+| string        | &times;      |     |
+| empty string        | &times;     |     |
+| 0             |  &times;     |   |
+| 1 or 2 or 3.14        | &times;     |     |
+| array       |  &times;   |     |
+| empty array        |  &times;    |     |
+| collection        | &times;     |    |
+| collection with no products        | &times;     |     |
+| page        | &times;     |     |
+| EmptyDrop        | &times;     |     |
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