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1537 :: ^ not working as expected

• DSblizzard (orginal) [2015-08-14T12:10:41+02:00] view original

  import math
  
  
  var n0: int = 10^7
  echo n0
  var n1: int = 10*10^7
  echo n1
  var n2: int = 10^8
  echo n2
  Run

  Output:

  10000000

  100000000

  Traceback (most recent call last)

  temp.nim(8) temp

  math.nim(346)

  system.nim(2988)

  Error: unhandled exception: over- or underflow [OverflowError]

  Error: execution of an external program failed

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• def (orginal) [2015-08-14T13:10:47+02:00] view original

  Works for me on 64bit, but not 32bit. I guess the compiler's VM calculates with 64bit numbers, but the final program with 32bit numbers. You can explicitly use a 64bit int like this:

  var n2 = (10'i64)^8
  Run

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• Jehan (orginal) [2015-08-14T14:28:36+02:00] view original

  It's a bug in the exponentiation implementation that does an unnecessary multiplication at the end for even exponents.

  Edit: Pull request for the fix has been submitted.

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