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14 :: Whats wrong with this template?

• ventor3000 (orginal) [2012-05-25T18:32:02+02:00] view original

  Need some help: compiling the code below fails with message: "test2.nim(2, 9) Error: invalid expression: 'while pos < s.len: " What am I doing wrong here?

  template test(a:seq[int],pos:var int):expr=

  while pos<a.len:

  echo(pos) inc pos

  var s= @[1,2,3]

  var pos=0

  test(s,pos)

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• dom96 (orginal) [2012-05-25T22:16:29+02:00] view original

  You are returning a 'expr' when you should be returning a 'stmt'.

  I have heard Araq mention that this difference will be removed in later versions of Nimrod as it is quite annoying. Key thing to remember for now is: if it's longer than one line, then it is a stmt, otherwise it's an expr.

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