reparse-coffeescript/examples/calc.coffee

30 lines
725 B
CoffeeScript
Raw Normal View History

ReParse = require('../src/reparse').ReParse
util = require("util")
class Calc extends ReParse
ignorews: true
OPS:
'+': (a, b) -> a + b
"-": (a, b) -> a - b
"*": (a, b) -> a * b
"/": (a, b) -> a / b
expr: => @chainl @term, @addop
term: => @chainl1 @factor, @mulop
factor: => @choice @group, @number
group: => @between '(', ')', @expr
number: => parseFloat @m(/^(\-?\d+(\.\d+)?)/)
mulop: => @OPS[@m(/^[\*\/]/)]
addop: => @OPS[@m(/^[\+\-]/)]
parse: =>
super
@start(@expr)
unless process.argv.length is 3
util.puts "Usage: node " + process.argv[1] + " expression"
process.exit 1
util.puts (new Calc).parse(process.argv[2])