Jade mixin default parameters

Question

I have a following mixin in Jade:

mixin indicator(slide_to, active)
  - active = active || '' // this is an ugly method to create a default value
  li(class=active, data-target='#' + CAROUSEL_ID, data-slide-to=slide_to)

and I call it like this:

+indicator(1) 
+indicator(2, 'active')

I want the parameter active to have a default value of ''. I have found the ugly workaround as is shown in my codesample. Is there a better way to do this in Jade?

Answer 1

This example:

mixin test(slide_to, active)
    li(class=active, data-slide-to=slide_to)

+test('a')
+test('a', 'b')

Compiles into this HTML for me:

<li data-slide-to="a"></li>
<li data-slide-to="a" class="b"></li>

I'm using Jade 0.35.0.

Jade doesn't add falsy values. You can read this in the Jade reference in the subchapter Boolean Attributes.