I think using Unicode is fine if your language guarantees support for it. (E.g. it is in the language standard.) Ultimately, something like τ -> τ' is much mor

I think using Unicode is fine if your language guarantees support for it. (E.g. it is in the language standard.) Ultimately, something like τ -> τ' is much more readable than tau -> tau' and is about as easy to type in a decent text editor (e.g. \tau -> \tau'). This is especially true for heavily mathematical code.