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9022 :: Case (switch) statement and modulo

• chikegar (orginal) [2022-03-19T04:41:01+01:00] view original

  Hi, I'm learning nim and decided to translate some FizzBuzz code from Basic that uses Case(switch) vs If Else If.

  Here's the Basic syntax:

   i = 1 to 100
      select case
          case i mod 15 = 0
              print "FizzBuzz"
          case i mod 3 = 0
              print "Fizz"
          case i mod 5 = 0
              print "Buzz"
          case else
              print i
      end select
  next i
  Run

  My attempt at replicating the Basic code in nim:

   i in 1 .. 100:
    case i
    of i mod 15 == 0:
      echo "FizzBuzz"
    of i mod 3 == 0:
      echo "Fizz"
    of i mod 5 == 0:
      echo "Buzz"
    else:
      echo i
  Run

  I'm getting the error: "Error: cannot evaluate at compile time: i ". I realize some languages do not support Case(switch) statements with the use of some conditional expressions like the modulo operator and was wondering if that's the case (no pun intended) with the nim language. Thanks in advance. :)

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• shirleyquirk (orginal) [2022-03-19T13:44:17+01:00] view original

  The of expression needs to be calculable at compile time.

  You could use if/elif, or:

  for i in 1 .. 100:
    
    case i mod 15:
    
    of 0:
      
      echo "FizzBuzz"
    
    of 3,6,9,12:
      
      echo "Fizz"
    
    of 5,10:
      
      echo "Buzz"
    
    else:
      
      echo i
  Run

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• DeletedUser (orginal) [2022-03-19T13:50:01+01:00] view original

  You want if/elif/else.

  for i in 1 .. 100:
    if i mod 15 == 0:
      echo "FizzBuzz"
    elif i mod 3 == 0:
      echo "Fizz"
    elif i mod 5 == 0:
      echo "Buzz"
    else:
      echo i
  Run

  Manual

  There are many basic Nim tutorials online. The Nim website lists some of them.

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• SolitudeSF (orginal) [2022-03-19T14:15:37+01:00] view original

  how is that select/case different from if/elif?

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• chikegar (orginal) [2022-03-19T22:53:07+01:00] view original

  Thanks everyone! Always more than one way to skin a cat. I have to say that I'm am dabbling in several languages at the same time - some older languages and some newer ones. As I progress, I'm finding that, in general, some allow case (switch) expressions that are not known at compile time and some languages require the expressions be known at compile time. C and C-based languages generally appear to fall in latter camp. nim compiles to C and C-based languages, so this would make sense. Looking at Rosetta Code, it's interesting to see all the variations and solutions for "FizzBuzz" - some very straightforward, some very clever and some very obscure .. but in general the languages appear to vacillate mainly between case/switch/match and if else (if). But there are some languages that can accommodate both constructs. I'm the guy who submitted the FizzBuzz code for Vlang using both constructs. ;) I can't tell you what the advantages of one construct is over the other and there is probably no right or wrong way for day-to-day general programming. Maybe there is a discernable difference in the realm of embedded programming. I was just simply curious about what nim allows or does not allow, so I can make a note in the back of my head while I learn it. Of the newer languages that I'm learning though, I find nim to be a very pleasant experience. So, Cheers nim peeps! :)

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