Adds backslashes before quotation marks to escape them.

Variable

blurb = "Where'd you get the coconuts?"

Template

{{ blurb|addslashes }}

Result

Where\'d you get the coconuts?

This is particularly useful when you need to include Django variables within JavaScript code. Consider the following:

Template

<button onclick="alert('{{ blurb }}')">Alert</button>

Result

<button onclick="alert('Where'd you get the coconuts?')">Alert</button>

This will result in a JavaScript bug as the apostrophe in Where'd will close the JavaScript string. Using addslashes will fix that:

<button onclick="alert('{{ blurb|addslashes }}')">Alert</button>

Result

<button onclick="alert('Where\'d you get the coconuts?')">Alert</button>

Notice that the apostrophe in Where'd is now escaped.