Sometimes when it’s false, it’s true

Posted 6th May 2022 in Development and HTML

A short posts on boolean attributes in HTML. What’s a boolean attribute? Something that can only be true or false false; things like:

They either are reversed, checked or disabled, or they’re not.

The funny thing about booleans in HTML is that they’re true if they exist. So even if the value is false (like required="false") it’s still true!

In fact, it doesn’t matter what value a boolean attribute is given: required="true", required="false", and required="banana" do the same thing.

You can go one step further an remove the value altogether, leaving just required, and that’s what I do. It differentiates a boolean nicely from other attributes like class and src.

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