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3903 :: Weird compiler error in echo() with variadic expressions?

• aedt (orginal) [2018-06-09T01:26:57+02:00] view original

  
  static:
    type range = array[1 .. 100, bool]
    
    var doors: range;
    
    for i in doors.low() .. doors.high():
      doors[i] = false
    
    proc toggle(b: var bool) {.inline.} = b = if b: false else:  true
    
    for i in doors.low() .. doors.high():
      for j in countup(i, 100, i):
        doors[j].toggle()
  
  for i, door in doors:
    echo i, " is", (if door: "open" else: "closed"), "."
  Run

  The line above complains:

  
  ... Error: execution of an external compiler program 'gcc -c  -w  -I/home/user0/.choosenim/toolchains/nim-0.18.0/lib -o /home/user0/devel/atom/nim/app/
  src/nimcache/app_hundreddoors.o /home/user0/devel/atom/nim/app/src/nimcache/app_hundreddoors.c' failed with exit code: 1
          ... /home/user0/devel/atom/nim/app/src/nimcache/app_hundreddoors.c: In function ‘app_hundreddoorsInit000’:
          ... /home/user0/devel/atom/nim/app/src/nimcache/app_hundreddoors.c:115:38: error: ‘doors_w1Wm3phlUyGhRDq4wvpsuQ’ undeclared (first use in this function
  )
          ...       door_gIfeUZM6XK9aj8VoS9asjlLA = doors_w1Wm3phlUyGhRDq4wvpsuQ[(i)- 1];
          ...                                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
          ... /home/user0/devel/atom/nim/app/src/nimcache/app_hundreddoors.c:115:38: note: each undeclared identifier is reported only once for each function it
  appears in
  Run

  Is is this a compiler issue?

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• DeletedUser (orginal) [2018-06-09T05:10:59+02:00] view original

  Like this:

  const doors = block:
    type range = array[1 .. 100, bool]
    
    var doors: range
    
    for i in doors.low() .. doors.high():
      doors[i] = false
    
    proc toggle(b: var bool) {.inline.} = b = not b #if b: false else:  true
    
    for i in doors.low() .. doors.high():
      for j in countup(i, 100, i):
        doors[j].toggle()
    
    doors
  
  for i, door in doors:
    echo i, " is ", (if door: "open" else: "closed"), "."
  Run

  Unrelated, but you don't need to inline the toggle proc since it's running in the nim VM and doesn't need much premature optimization. Also that type alias can be fairly confusing since range is already a type in Nim

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