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3114 :: Inputing numbers

• jzakiya (orginal) [2017-08-21T01:07:26+02:00] view original

  I want to input numbers into a program from the command line.

  
  $ ./myprogram
  Please iput number:
  <do program>
  Run

  The input number are unsigned 64-bit (uint64)

  I tried the following:

  
  let var = uint64(readling(stdin, input)
  Run

  But I apparently have to convert a string to an uint.

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• mashingan (orginal) [2017-08-21T01:37:55+02:00] view original

  Use parseBiggestUInt proc in strutils?

  You can do like this:

  import strutils
  
  let theint = stdin.readline.parseBiggestUInt
  Run

  or

  import strutils
  
  var theint = -1'u64
  try:
    theint = stdin.readline.parseBiggestUInt
  except ValueError:
    # do something
  Run

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• jzakiya (orginal) [2017-08-21T04:11:29+02:00] view original

  These don't work.

  When the program displays

  
  Enter number value:
  Run

  it should stay there until I type a number and hit <enter> and then proceed. For both cases shown the program just falls through.

  
  [jzakiya@jabari-pc nim]$ ./myprogram
  Enter number value:
  Error: unhandled exception: Unknown IO Error [IOError]
  Run

  Essentially, I want to do the equivalent C++ code below to enter nunbers.

  
  cout << "Enter number value: ";
  uint64 val;
  cin >> val;
  Run

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• mashingan (orginal) [2017-08-21T04:31:28+02:00] view original

  How do you write your code? AFAIK, readLine is blocking.

  In my machine, below code is working fine. Using Windows 10 with GCC v 7.1.0

  import strutils, typetraits
  
  stdout.write "Input integer number: "
  let number = stdin.readline.parseBiggestUInt
  echo "You inputed ", number, " with type ", number.type.name
  Run

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• jzakiya (orginal) [2017-08-21T05:50:26+02:00] view original

  I'm am running Manjaro KDE (gcc 7.1.1, clang 4.0.1) in a VirtualBox VM using another Linux distros as VB host.

  When I run this file:

  inputtest.nim

  
  import strutils, typetraits
  
  stdout.write "Enter integer number: "
  let val = stdin.readline.parseBiggestUInt
  echo "You inputed ", val, " with type ", val.type.name
  Run

  Here are the compile and runtime results

  
  [jzakiya@jabari-pc nim]$ nim c --cc:clang --d:release  inputtest.nim
  Hint: used config file '/etc/nim.cfg' [Conf]
  Hint: system [Processing]
  Hint: inputtest [Processing]
  Hint: strutils [Processing]
  Hint: parseutils [Processing]
  Hint: math [Processing]
  Hint: algorithm [Processing]
  Hint: typetraits [Processing]
  CC: inputtest
  CC: stdlib_system
  CC: stdlib_strutils
  CC: stdlib_typetraits
  CC: stdlib_parseutils
  CC: stdlib_math
  CC: stdlib_algorithm
  Hint:  [Link]
  Hint: operation successful (14862 lines compiled; 0.920 sec total; 17.938MiB peakmem; Release Build) [SuccessX]
  [jzakiya@jabari-pc nim]$ ./inputtest.nim
  bash: ./inputtest.nim: Permission denied
  [jzakiya@jabari-pc nim]$
  Run

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• jzakiya (orginal) [2017-08-21T06:04:15+02:00] view original

  Whoops, sorry, forgot to run the executable (probably should go to bed now)

  
  [jzakiya@jabari-pc nim]$ ./inputtest
  Enter integer number: 34422
  You inputed 34422 with type BiggestUInt
  [jzakiya@jabari-pc nim]$
  Run

  Made the same mistake on target program, but it works now too. Definitely time to go to bed now.

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