coffeescript throw Error("ExecJS::RuntimeError: SyntaxError: unexpected , in function

Question

I have written this function in coffeescript:

doCalculate = (old, new) ->
  difference = roundNumber (old - new, 5)

but when compiled generates the error:

throw Error("ExecJS::RuntimeError: SyntaxError: unexpected ,

If I remove the , 5 part I get no error any more.

I can't figure what's wrong with a comma.

The function roundNumber is defined as follows, in the same file:

 roundNumber = (rnum, rlength = 6) ->
   pow = Math.pow( 10, rlength )
   newnumber = Math.round ( rnum * pow ) / pow
   parseFloat(newnumber)

The error happens regardless I use the default value in rlength or not. — Don Giulio
– Don Giulio, Commented Jun 11, 2013 at 10:18
possible duplicate of Coffeescript: invoking function with space before parens — mu is too short
– mu is too short, Commented Jun 11, 2013 at 16:10

Don Giulio · Accepted Answer · 2014-01-16 17:15:58Z

3

ahhhh I figured it out. coffeescript requires that there is no space between the function name and the open parenthesis.

it even works with no parentheses at all.

but not if there's a space between the function name and the (.

this works:

difference = roundNumber old - new, 5

Thanks :)

answered Jun 11, 2013 at 10:23

Don Giulio

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