Copyright	(C) 2013-14 Edward Kmett
License	BSD-style (see the file LICENSE)
Maintainer	Edward Kmett <ekmett@gmail.com>
Stability	provisional
Portability	Control.Exception
Safe Haskell	Safe-Inferred
Language	Haskell98

System.Exit.Lens

Description

These prisms can be used with the combinators in Control.Exception.Lens.

Synopsis

Documentation

class AsExitCode p f t where Source

Exit codes that a program can return with:

Minimal complete definition

Nothing

Methods

_ExitCode :: Optic' p f t ExitCode Source

_ExitCode :: Equality' ExitCode      ExitCode
_ExitCode :: Prism'    SomeException ExitCode

Instances

(Choice p, Applicative f) => AsExitCode p f SomeException
AsExitCode p f ExitCode

_ExitFailure :: (AsExitCode p f t, Choice p, Applicative f) => Optic' p f t Int Source

indicates program failure with an exit code. The exact interpretation of the code is operating-system dependent. In particular, some values may be prohibited (e.g. 0 on a POSIX-compliant system).

_ExitFailure :: Prism' ExitCode      Int
_ExitFailure :: Prism' SomeException Int

_ExitSuccess :: (AsExitCode p f t, Choice p, Applicative f) => Optic' p f t () Source

indicates successful termination;

_ExitSuccess :: Prism' ExitCode      ()
_ExitSuccess :: Prism' SomeException ()