./odin-calc
>>> 1 + 2 * 2 + -(3 + 2) * 2
  = -5.000000

>>> exit

for fun 👍

• ascii input
• operator precedence
• unary plus and minus (currently it is part of a number, not an operator)
• predefined constatns (pi, tau, e)
• nested parentheses (implemented via recursion, so it may stack overflow)

• unicode input
• nice error message
• non-interactive mode
• user defined variables
• predefined functions
• user defined functions
• user defined operators
• simple line edit capabilities (similar to linenoise)
• more cool ideas...