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9094 :: Result of applying high()/low() to a range typedesc

• dxb (orginal) [2022-04-09T12:43:22+02:00] view original

  Hi!

  I tried defining a range as type and then used high() and low() to get the interval's upper and lower bounds. I found that high() and low() return a range type value while I would have expected the return value to be of the type of the underlying ordinal type for the range's bounds. Converting to result to int works (see below) but I am wondering:

  1. Is this the "right thing (tm)" to do?
  2. Is it desirable for high(range) to return a range instead of an ordinal? Signature of the low() function here.
  3. Is there a better way?

  $ nim secret
  >>> type R = 1..10
  >>> low(R)
  1: R
  >>> high(R)
  10: R
  >>> type(high(R))
  R: typedesc[R]
  >>> int(low(R))
  1: int
  Run

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• Yardanico (orginal) [2022-04-09T12:45:37+02:00] view original

  I think it's the right thing to do, since high/low are used for example for enums:

  type
    MyEnum = enum
      Small, Medium, Large
  
  echo low(MyEnum)
  echo high(MyEnum)
  Run

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• dxb (orginal) [2022-04-09T13:25:21+02:00] view original

  Also, range types are implicitly convertible to their parent ones, so it's not such a big deal:

  Acknowledged, thank you for the reply! :D

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