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14076 :: compiles, range, nimony and playground

• dwhall256 (orginal) [2026-07-22T18:46:31+02:00] view original

  I have this code where I'm using range to make illegal values unrepresentable:

  
  type Bitflags*[Nb: static int] = object
    flags: array[(Nb + 31) div 32, uint32]
  
  func incl*[Nb: static int](self: var Bitflags[Nb], flagIdx: range[0 .. (Nb - 1)]) =
    discard
  
  var bf = Bitflags[60]()
  
  #bf.incl(100) # Error: conversion from int literal(100) to range 0..59(int) is invalid
  assert not compiles(bf.incl(100))
  Run

  My goal is to have a unit test confirm this should not compile (I've used assert here as a stand-in for a unittest check).

  My questions:

  1. The commented-out line results in an error from the compiler, so compiles should return false, right? Does this merit a github issue?
  2. Is range on Nimony's roadmap, backburner or no-fly list? (not trying to poke a sore spot, just seeking guidance)

  Lastly, I'm only seeing Nim versions 1.X.X on the playground. Anybody else seeing this?

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