Nim/tests/effects/teffects1.nim

discard """
  cmd: "nim check --hint:Conf:off --hint:XDeclaredButNotUsed:off $file"
  nimout: '''
teffects1.nim(17, 28) template/generic instantiation from here
'''
"""
{.push warningAsError[Effect]: on.}
type
  TObj {.pure, inheritable.} = object
  TObjB = object of TObj
    a, b, c: string

  IO2Error = ref object of IOError

proc forw: int {. .}

proc lier(): int {.raises: [IO2Error].} = #[tt.Hint
                            ^ 'lier' cannot raise 'IO2Error' [XCannotRaiseY] ]#
  writeLine stdout, "arg" #[tt.Error
  ^ writeLine stdout, ["arg"] can raise an unlisted exception: ref IOError ]#

proc forw: int =
  raise newException(IOError, "arg")

block:
  proc someProc(t: string) {.raises: [Defect].} =
    discard
  let vh: proc(topic: string) {.raises: [].} = someProc

{.push raises: [Defect].}

type
  MyProcType* = proc(x: int): string #{.raises: [ValueError, Defect].}

proc foo(x: int): string {.nimcall, raises: [ValueError].} =
  if x > 9:
    raise newException(ValueError, "Use single digit")
  $x

var p: MyProcType = foo #[tt.Error
                    ^
type mismatch: got <proc (x: int): string{.nimcall, raises: [ValueError], noSideEffect, gcsafe.}> but expected 'MyProcType = proc (x: int): string{.closure.}'
  Calling convention mismatch: got '{.nimcall.}', but expected '{.closure.}'.
.raise effects differ
]#
{.pop.}
{.pop.}