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891 :: set array size - cannot evaluate at compile time

• kuba (orginal) [2015-02-18T19:03:01+01:00] view original

  Hi there, I'm getting a compiler error: Error: cannot evaluate at compile time: arrLength Any ideas why this is happening? Thanks

  var arrLength = 3
  var aaa : array[arrLength,uint8]
  Run

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• andrea (orginal) [2015-02-18T19:07:16+01:00] view original

  Although arrLength is written in the source file, it is a var, which is a runtime construct. You can replace it with a const and it should work

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• kuba (orginal) [2015-02-18T19:22:43+01:00] view original

  Thanks, that works , but how about this:

  
  arrLength = k*3
  Run

  when k is a value defined at a runtime?

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• pwernersbach (orginal) [2015-02-18T19:36:36+01:00] view original

  Arrays in Nim can only have static sizes that are determined at compile time. If you need an array that has a size determined at runtime, you need to use a sequence (also know as a seq). Sequences function just like arrays, but the definition is different:

  var arrLength = foo
  var aaa: seq[uint8] = newSeq[uint8](arrLength)
  
  aaa[0] = bar1
  aaa[1] = bar2
  Run

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