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7589 :: Sorting array by object key

• drkameleon (orginal) [2021-03-08T10:37:22+01:00] view original

  So, the scenario is this:

  I have an array (ValueArray) of Value`s. (which is a `ref object with a d OrderedTable field).

  Long story short, I want to sort this array of Values by dictionary key.

  So... this is what I've done:

  let sorted: ValueArray = x.a.sorted(
         proc (x, y: (Value,Value)): int =
                 cmp(x.d[aBy], y.d[aBy]), order=SortOrder.Descending)
  Run

  where aBy is the key by which I want to sort this array of tables.

  However, the compiler seems not to know that x and y being Value`s have a `d field:

  
  Error: undeclared field: 'd'
  Run

  How do I deal with this?

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• aEverr (orginal) [2021-03-08T10:42:14+01:00] view original

  did you export d? d*: OrderedTable[...] (note the asterisk)

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• drkameleon (orginal) [2021-03-08T10:44:03+01:00] view original

  Yes, of course. The Value objects (and their fields) are being used in hundreds of different places across the project.

  For some reason, it's inside the custom cmp proc that they're not recognized.

  P.S. In case it matters, the code in question is inside a template.

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• drkameleon (orginal) [2021-03-08T10:50:23+01:00] view original

  I just spotted it myself! Jesus.

  This is the correct one:

  let sorted: ValueArray = x.a.sorted(
        proc (v1, v2: Value): int =
               cmp(v1.d[aBy.s], v2.d[aBy.s]), order=order)
  Run

  I was using (Value,Value) (a tuple) for the custom cmp proc. And while this valid for sorting OrderedTable instances, it's obviously not for sorting simple arrays.

  Thanks a lot for looking into it. My bad!

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