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4662 :: Procedural type and 'func' keyword

• thenjip (orginal) [2019-02-16T15:37:59+01:00] view original

  Hi,

  I want to declare a function that takes another one as its parameter.

  func someFunc(f: func(): bool): bool =
    f()
  Run

  So I expect someFunc and f to have the noSideEffect pragma.

  import std/typetraits
  
  echo someFunc.type()
  Run

  But only someFunc has it, not its parameter.

  proc (f: proc (): bool{.closure.}): bool{.noSideEffect, gcsafe, locks: <unknown>.}
  Run

  Speaking of side effect, this affects lambdas too.

  echo type(func (): bool)
  Run

  proc (): bool{.closure.}
  Run

  So, is it a bug ?

  Although it is not a big deal since the first func in someFunc enforces f to have no side effects.

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• mratsim (orginal) [2019-02-17T13:12:47+01:00] view original

  Seems like a bug

  func someFunc(f: func(): bool {.nimcall, noSideEffect.}): bool =
    f()
  
  echo someFunc.type() # proc (f: proc (): bool{.noSideEffect.}): bool{.noSideEffect, gcsafe, locks: 0.}
  Run

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• thenjip (orginal) [2019-02-17T14:25:16+01:00] view original

  Thanks for the reply.

  func someFunc(f: func(): bool {.nimcall, noSideEffect.}): bool =
    f()
  Run

  This is the workaround I use (nimcall or closure) and it does the job, though a bit repetitive.

  I forgot to tell the compiler version I used: 0.19.4.

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