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3500 :: Json key names encoding

• frogEye (orginal) [2018-01-24T10:47:23+01:00] view original

  I have looking for a way to encode the json keys, but has not been able to find anything on that.

  For example Go lets us do this

  type Response2 struct {

  Page int json:"page" Fruits []string json:"fruits"

  }

  I want to unmarshal a json object but not able to encode the json keys. As my key name start with number I am not able to have the same variable in json.

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• cdome (orginal) [2018-01-24T11:31:29+01:00] view original

  Latest Nim dev has custom pragmas that can be useful in this case.

  Details at the bottom of https://github.com/nim-lang/Nim/blob/devel/doc/manual/pragmas.txt

  Examples:

  https://github.com/nim-lang/Nim/blob/devel/tests/pragmas/tcustom_pragma.nim

  it could be not the only solution through

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• dom96 (orginal) [2018-01-24T23:37:45+01:00] view original

  You should do this: https://nim-lang.org/docs/json.html#dynamically-retrieving-fields-from-json

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• frogEye (orginal) [2018-01-25T11:09:57+01:00] view original

  Thanks, dom96 . But still, the ease with which we can unmarshal and marshal json into a data structure in Go-lang is uncomparable.

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• yglukhov (orginal) [2018-01-25T12:08:33+01:00] view original

  @frogEye. That is true because nim ideology differs a lot from go. Instead of providing some high level feature the nim compiler will tend to provide you with rich metaprogramming capabilities, and with those you can implement high level features that look and feel like native nim constructs. E.g. async/await paradigm is implemented in Nim in library code, whereas most languages with this paradigm enabled provide it on the compiler level. That said, recently introduced custom annotations allow you to implement json serialization ala go, as well as a ton of other serializations and what not.

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• frogEye (orginal) [2018-01-25T13:35:01+01:00] view original

  Thanks yglukhov for the reply. It just an observation as I have just started with nim-lang. So may be I was looking at things which I could do really fast in go to be in nim. I will take some time to get used to nim :)

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• dom96 (orginal) [2018-01-25T21:37:42+01:00] view original

  Nim offers similar functionality via the to macro, but indeed it doesn't support fields that begin with a number. I created an issue for this: https://github.com/nim-lang/Nim/issues/7139.

  Depending on your JSON you may be able to use a combination of the approach I described above and the to macro.

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• frogEye (orginal) [2018-01-29T10:36:22+01:00] view original

  Thanks @dom96

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