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540 :: Problem with indentation in factorial program

• sanjay (orginal) [2014-09-01T21:02:16+02:00] view original

  I tried to run following program from tutorial:

  const fac4 = (var x = 1; for i in 1..4: x *= i; x)
  Run

  It works fine. I re-wrote it as (no change in logic or identifiers):

  const fac4 = (
    var x = 1;
    for i in 1..4: x *= i;
    x)
  Run

  It also worked fine. However when I indented the for loop as in following code, it throws compile error for last line x) Error: ')' expected

  const fac4 = (
    var x = 1;
    for i in 1..4:
      x *= i;
    x)
  Run

  What is the reason for error?

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• Araq (orginal) [2014-09-02T06:45:50+02:00] view original

  (;;) has been designed for 1-liners. I thought complex indentation within it makes it too ambiguous and so disallowed it.

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• sanjay (orginal) [2014-09-02T11:16:48+02:00] view original

  Thanks Araq, can't it be extended to expression as shown in the last piece of code or will it be supported in future?

  Following line definitely provides a clean interface in terms of writing logic that need to be assigned to a variable without worrying about two different syntax to remember :

  var x = ( ....
                .....
              )
  Run

  Am I thinking something wrong?

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• Araq (orginal) [2014-09-02T12:32:01+02:00] view original

  Sure it can be extended in the future, but you're the first one who complains about it. ;-) Here's one reason why most people are already happy: There is nothing clean about

  
  var x = (echo "foo"; 13)
  Run

  when there is already

  
  echo "foo"
  var x = 13
  Run

  Note that both yield a void type, so it's not like composition works any better with var x = (;;).

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• sanjay (orginal) [2014-09-02T14:18:10+02:00] view original

  Hi Araq, frankly as you said, there will not be a need to do such assignments as there are better ways to do it.

  Thanks for clarification.

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