- no operator precedence; left-to-right only (this is a Feature) - grouping determined by spacing. Ex: 1/ 2+2 -> 0.25 - uses 128 bit DECIMAL floating point (34 digits) Run `make`, then `./calc` (requires a c compiler, and the readline library) Code is in `calc.c`. `calc.c++` and `main.lua` were experiments. Parsing: spaces after an operator are treated as `(` (closed automatically at end of expression) spaces before an infix operator are treated as `)` (if there are open parentheses) Ex: 1+2 / 3+4 -> (1+2)/(3+4) -1^ 2+2 /3 -> -1^(2+2)/3 - 5+10 -> -(5+10) Operators: infix: + - * / % ^ prefix: - (more can be added easily) Values: numbers must start with a digit or decimal point, then parsed by `strtod`. `a` refers to the result of the previous expression reminded by https://github.com/ninedotnine/happy-space