ERT Test

This is a test for Evil Red Test (TeX code).
Pure TeX can contain formulas: Equation a = b. This activates the dorky math mode.
It can also contain arbitrary commands: $ http://elyxer.nongnu.org/.
ERTs can be left open and be closed afterwards . This allows us to apply commands to arbitrary text: this text should be red, http://should.be.an.url/.
ERTs can also be inserted in formulas:
(unnumbered) a = b.
A rule in an ERT:
.
Other commands can be ignored: .