Julia has a few Unicode operators and will allow you to tabcomplete the LaTeX symbol in the REPL [1]. For example, \div followed by TAB becomes ÷. This can be implemented in popular editors [2].

[1] Not all are the common LaTeX macros. See http://docs.julialang.org/en/latest/manual/unicode-input/

[2] https://github.com/JuliaLang/julia-vim

I personally use XCompose and I'm eyeing the media keys on my keyboard as potential single-key operators. But you don't have to use fancy Unicode and can just use Texas variants.

https://github.com/rrthomas/pointless-xcompose perhaps?