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