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8768 :: 2 questions on json mudule

• oyster (orginal) [2022-01-04T08:03:22+01:00] view original

  1st question

  for the code, I expected the latter output is

  
  21
  HELLO
  Run

  however, the real one is

  
  21
  
  20
  HELLO
  20
  Run

  why 20 appears?

  the code

  import strUtils
  import json
  
  var a = %*[1, "hello", nil]
  
  echo a
  echo "\n"
  
  for i in a.items():
      echo i, " ", i.type
  echo "\n"
  
  for i in a.items():
      if i.getInt() is int:
          echo (i.getInt() + 20)
      if i.getStr() is string:
          echo i.getStr().toUpper
  Run

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• DeletedUser (orginal) [2022-01-04T08:08:39+01:00] view original

  i.getInt() is int checks the type of the expression i.getInt() and checks if it matches int, so this condition is always true. You want i.kind == JInt and i.kind == JString. json docs

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• oyster (orginal) [2022-01-04T08:13:06+01:00] view original

  the 2nd question is, can we get the underground value of JsonNode? so that I can do

  
  for i in a.getUnderGround():
      if i is int:
          echo (i + 20)
      if i is string:
          echo i.toUpper
  Run

  I asked so question, because I met a C# code which I try to mimic in nim

  I know nimlang is a static language, and I have read Is there any untyped list data type in Nim ?, like in python.<https://forum.nim-lang.org/t/4233>`_

  I know nothing about C#, but a quick search says that C# is a statically-typed language. However the following code looks something unusual, at least for me.

  #
          static Object[,] sample_data = {
              {"Yegor Kozlov", "YK", 5.0, 8.0, 10.0, 5.0, 5.0, 7.0, 6.0},
              {"Gisella Bronzetti", "GB", 4.0, 3.0, 1.0, 3.5, null, null, 4.0}
          };
  
  for (int i = 0; i < sample_data.GetLength(0); i++)
              {
                  IRow row = sheet.GetRow(2 + i);
                  for (int j = 0; j < sample_data.GetLength(1); j++)
                  {
                      if (sample_data[i, j] == null)
                          continue;
                      
                      if (sample_data[i, j] is String)
                      {
                          row.GetCell(j).SetCellValue((String)sample_data[i, j]);
                      }
              }
  
  Run

  thanks

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• PMunch (orginal) [2022-01-04T08:40:50+01:00] view original

  The answer to this question is the same as the answer to the first question. Use the kind attribute of your JsonNode to see what kind of JSON node it is.

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• kobi (orginal) [2022-01-04T12:10:01+01:00] view original

  For your example:

  
  import strUtils
  import json
  
  var a = %*[1, "hello", nil]
  
  echo a
  echo "\n"
  
  for i in a.items():
      echo i, " ", i.kind
  echo "\n"
  
  for i in a.items():
      case i.kind
      of JInt:
          echo (i.getInt() + 20)
      of JString:
          echo i.getStr().toUpper
      of JNull:
          discard
      else:
          assert false, "unsupported"
  Run

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• oyster (orginal) [2022-01-05T03:16:18+01:00] view original

  thanks, everyone the json module saves a lot of typing for my case

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