Add defer attribute to javascript_include_tag Rails

Question

Is there some way to add the defer attribute easily using the javascript_include_tag helper in Rails?

I.e., is there some easy way to turn

<%= javascript_include_tag "blah.js" %>

into

<script defer src="blah.js"></script>

emrass · Accepted Answer · 2012-06-11 15:21:27Z

54

<%= javascript_include_tag "blah.js", :defer => "defer" %>

This will get you (in development):

<script defer="defer" src="/assets/blah.js" type="text/javascript"></script>

answered Jun 11, 2012 at 15:21

emrass

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4 Comments

For those interested, here is the link to the docs: w3.org/TR/html4/interact/scripts.html#edef-SCRIPT

This also works great with middleman which also uses sprokets / asset pipeline.

Strange, they don't have any example of async and difer in APIDoc :\

A bit simpler, same result: <%= javascript_include_tag "blah.js", defer: true %>

Obromios · Accepted Answer · 2017-01-12 23:48:34Z

38

You can also do

<%= javascript_include_tag "blah.js", defer: true %>

which is more consistent with other switches.

answered Jan 12, 2017 at 23:48

Obromios

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