Yep. Mathematica is what I think about when I hear TRS. There is a good video by a Gaylord something or another where he explains how the Wolfram Mathematica language evaluates expressions.

Mathematica is extremely powerful and very cool. The only thing that isn't cool is the fact that it's commercial.

Edit: Found the video https://youtu.be/H-rnezxOCA8?feature=shared