+++
title = "Functions"
linkTitle = "Engine Functions"
[menu.main]
parent = "engine"
weight = 4
+++

While [extensions]({{< relref "engine/extensions.md" >}}) are awesome for adding additional reusable functionality to Plates, sometimes it's easier to just create a one-off function for a specific use case. Plates makes this easy to do.

## Registering functions

~~~ php
// Create new Plates engine
$templates = new \League\Plates\Engine('/path/to/templates');

// Register a one-off function
$templates->registerFunction('uppercase', function ($string) {
    return strtoupper($string);
});
~~~

To use this function in a template, simply call it like any other function:

~~~ php
<h1>Hello <?=$this->e($this->uppercase($name))</h1>
~~~

It can also be used in a [batch]({{< relref "templates/functions#batch-function-calls">}}) compatible function:

~~~ php
<h1>Hello <?=$this->e($name, 'uppercase')</h1>
~~~