bc

I liked using bc when I was on Ubuntu. I'm cloning it in Rust so that I'll be able to use it in every OS I use.

Also, learning interpreters / compilers.

TODO

Tokenizer
AST generation
- Parser / Compiler rewrite
Actual interpretation (stack machine)
Global variables
Proper error handling.
Big-Number Arithmetics (scale)
Functions (define)
- Local environment for local variables?
- BUG: Check the arity of the called function. For example sqrt(5, 4) works and generates a PushConstant(4) instruction!
Standard Library
UTF-8 support
Support for econometry stuff?
- Arrays
- Statistical Functions
- What else?