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6282 :: Exporting json objects to Javascript, how can I make this code more terse?

• hiteshjasani (orginal) [2020-05-02T02:19:05+02:00] view original

  I'm trying to create a json object that is exported and available to other Javascript libraries. Here's a trivial example below. The code below works, I can generate the js file, access the exported vars in the browser js console and it works with my other library.

  But I wish it weren't so verbose. My real json objects will be much larger, more deeply nested and have many more variations in format. I really like the %* macro in the json module, but the js it generates is not in a format that other libraries can use.

  How can this be improved?

  import jsffi
  
  # {
  #   "friends": [
  #     {
  #       "val": 19,
  #       "name": "wendy",
  #       "lang": "nim"
  #     }
  #   ],
  #   "name": "sam",
  #   "val": 21
  # }
  
  proc makeObj1(): JsObject =
    result = newJsObject()
    result.val = 19
    result.name = cstring"wendy"
    result.lang = cstring"nim"
  
  proc makeObj2(): JsObject =
    result = newJsObject()
    result.friends = [
      makeObj1()
    ]
    result.name = cstring"sam"
    result.val = 21
  
  var myobj2 {.exportc: "myobj2".} = makeObj2()
  Run

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• juancarlospaco (orginal) [2020-05-02T03:03:52+02:00] view original

  Compile with -d:danger and put name on everything relevant with {.exportc.}.

  Your code will probably go thru a Minifier anyways, so maybe better focus on tests and documentation.

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• hiteshjasani (orginal) [2020-05-02T03:05:41+02:00] view original

  Some more research turned up a macro in jsffi that works the way I want. Here's the improved code.

  import jsffi
  
  type
    Person = ref object of JsObject
      name: cstring
      val: int
      lang: cstring
    
    Rec = ref object of JsObject
      name: cstring
      val: int
  
  let obj1 {.exportc: "obj1".} = Rec{
    friends: [
      Person{
        val: 19,
        name: "wendy",
        lang: "nim"
      }
    ],
    name: "sam",
    val: 21
  }
  
  var myobj1 {.exportc: "myobj1".} = obj1
  Run

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