{% if %}

The {% if %} and {% endif %} tags will represent an expression and is comparable with the if statements of PHP. In the simplest form you can use it to test if an expression evaluates to true:

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    <p>The website is in maintenance mode.</p>
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You can also test if an array is not empty:

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    <ul>
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            <li>___TWIG2___</li>
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    </ul>
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Note: If you want to test if the variable is defined, use {% if users is defined %} instead.

You can also use not to check for values that evaluate to false:

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    <p>You are not subscribed to our mailing list.</p>
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For multiple expressions {% elseif %} and {% else %} can be used:

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    Kenny is sick.
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    You killed Kenny! You bastard!!!
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    Kenny looks okay so far.
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# Expression rules

The rules to determine if an expression is true or false are the same as in PHP, here are the edge cases rules: