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 with text. 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.
Curly brackets can be inserted escaping them: { like this }. Also in a formula: {h}. Escaped curly brackets should not be confused with regular TeX brackets: {}.
A rule in an ERT:
.
Other commands can be ignored: . TeX comments should also be ignored: but not text between comments.