Copyright	(c) 2019-2021 Emily Pillmore
License	BSD
Maintainer	Emily Pillmore <emilypi@cohomolo.gy>
Stability	Experimental
Portability	TypeFamilies
Safe Haskell	None
Language	Haskell2010

System.Process.Lens.CmdSpec

Contents

Traversals
Prisms
Classy Prisms
Combinators

Description

This module provides the associated optics and combinators for working with CmdSpec objects. CmdSpec consists of two cases: a Shell command, which is a command to execute naively in the shell, and a Raw command which is a command path together with its arguments. As a result, CmdSpec has prisms into those two cases.

There is also a convenient Traversal available for working with the arglist of a Raw command, as well as associated Reviews for each prism, and combinators for working with arguments monoidally.

We provide classy variants for all useful prisms

Synopsis

arguments :: AsRaw a => Traversal' a [String]
_ShellCommand :: Prism' CmdSpec String
_RawCommand :: Prism' CmdSpec (FilePath, [String])
class AsShell a where
- _Shell :: Prism' a String
class AsRaw a where
- _Raw :: Prism' a (FilePath, [String])
arguing :: AsRaw a => String -> a -> a
shellOf :: AsShell a => String -> a
rawOf :: AsRaw a => FilePath -> [String] -> a

Traversals

arguments :: AsRaw a => Traversal' a [String] Source #

Traversal' into the arguments of a command

Examples:

>>> RawCommand "/bin/ls" ["-l"] ^. arguments
["-l"]

Prisms

_ShellCommand :: Prism' CmdSpec String Source #

A prism into the ShellCommand case of a CmdSpec

Examples:

>>> _ShellCommand # "ls -l"
ShellCommand "ls -l"

>>> ShellCommand "ls -l" ^? _ShellCommand
Just "ls -l"

>>> RawCommand "/bin/ls" ["-l"] ^? _ShellCommand
Nothing

_RawCommand :: Prism' CmdSpec (FilePath, [String]) Source #

A prism into the RawCommand case of a CmdSpec

Examples:

>>> RawCommand "/bin/ls" ["-l"] ^? _RawCommand
Just ("/bin/ls",["-l"])

>>> RawCommand "/bin/ls" ["-l"] ^? _ShellCommand
Nothing

>>> RawCommand "/bin/ls" ["-l"] ^. _RawCommand . _1
"/bin/ls"

>>> RawCommand "/bin/ls" ["-l"] ^. _RawCommand . _2
["-l"]

Classy Prisms

class AsShell a where Source #

Classy prism into the shell command of a CmdSpec

Examples:

>>> f :: AsShell a => a -> Maybe String; f = preview _Shell
>>> f $ _ShellCommand # "ls -l"
Just "ls -l"

Methods

_Shell :: Prism' a String Source #

Instances

Instances details

AsShell CmdSpec Source #
Instance details Defined in System.Process.Lens.CmdSpec Methods _Shell :: Prism' CmdSpec String Source #

class AsRaw a where Source #

Classy prism into the raw command of a CmdSpec

Examples:

>>> f :: AsRaw a => a -> Maybe FilePath; f = preview (_Raw . _1)
>>> f $ _RawCommand # ("/bin/ls", ["ls -l"])
Just "/bin/ls"

Methods

_Raw :: Prism' a (FilePath, [String]) Source #

Instances

Instances details

AsRaw CmdSpec Source #
Instance details Defined in System.Process.Lens.CmdSpec Methods _Raw :: Prism' CmdSpec (FilePath, [String]) Source #

Combinators

arguing :: AsRaw a => String -> a -> a Source #

Append an argument to the argument list of a RawCommand

Examples:

>>> arguing "-h" $ RawCommand "/bin/ls" ["-l"]
RawCommand "/bin/ls" ["-l","-h"]

>>> arguing "-h" (RawCommand "/bin/ls" ["-l"]) ^. arguments
["-l","-h"]

shellOf :: AsShell a => String -> a Source #

Lift a String into a type via ShellCommand with a prism into the

Examples:

>>> shellOf @CmdSpec "ls"
ShellCommand "ls"

rawOf :: AsRaw a => FilePath -> [String] -> a Source #

Lift a FilePath and list of arguments into a type via RawCommand with a prism into the command

Examples:

>>> rawOf @CmdSpec "/bin/ls" ["-l"]
RawCommand "/bin/ls" ["-l"]