How do I put a html tag conditional in jade?

Question

In jade, I want to put in a html tag conditional as per this method, which puts in

Answer 1

Starting at version 1.0.0, the // if construct is not magical anymore. Either render HTML verbatim (any line starting with < is transmitted as-is by Jade) or use a mixin, as per Tom's blog cited in another answer:

mixin ie(condition)
    | 

doctype html
html
  head
    title= My title
    +ie('if IE 8')
      link(rel='stylesheet', href='/stylesheets/style-ie8-1.css')