Distribution.Simple.Program

Cabal-1.6.0.3: A framework for packaging Haskell software

Distribution.Simple.Program

Portability	portable
Maintainer	cabal-devel@haskell.org

Contents

Program and functions for constructing them
Configured program and related functions
The collection of unconfigured and configured progams
The collection of configured programs we can run
Programs that Cabal knows about

Description

This provides an abstraction which deals with configuring and running programs. A Program is a static notion of a known program. A ConfiguredProgram is a Program that has been found on the current machine and is ready to be run (possibly with some user-supplied default args). Configuring a program involves finding its location and if necessary finding its version. There is also a ProgramConfiguration type which holds configured and not-yet configured programs. It is the parameter to lots of actions elsewhere in Cabal that need to look up and run programs. If we had a Cabal monad, the ProgramConfiguration would probably be a reader or state component of it.

The module also defines all the known built-in Programs and the defaultProgramConfiguration which contains them all.

One nice thing about using it is that any program that is registered with Cabal will get some "configure" and ".cabal" helpers like --with-foo-args --foo-path= and extra-foo-args.

There's also good default behavior for trying to find "foo" in PATH, being able to override its location, etc.

There's also a hook for adding programs in a Setup.lhs script. See hookedPrograms in Distribution.Simple.UserHooks. This gives a hook user the ability to get the above flags and such so that they don't have to write all the PATH logic inside Setup.lhs.

Synopsis

data Program = Program {

programName :: String

programFindLocation :: Verbosity -> IO (Maybe FilePath)

programFindVersion :: Verbosity -> FilePath -> IO (Maybe Version)

programPostConf :: Verbosity -> ConfiguredProgram -> IO [ProgArg]

}

simpleProgram :: String -> Program

findProgramOnPath :: FilePath -> Verbosity -> IO (Maybe FilePath)

findProgramVersion :: ProgArg -> (String -> String) -> Verbosity -> FilePath -> IO (Maybe Version)

data ConfiguredProgram = ConfiguredProgram {

programId :: String

programVersion :: Maybe Version

programArgs :: [ProgArg]

programLocation :: ProgramLocation

}

programPath :: ConfiguredProgram -> FilePath

type ProgArg = String

data ProgramLocation

= UserSpecified {

locationPath :: FilePath

}

| FoundOnSystem {

locationPath :: FilePath

}

rawSystemProgram :: Verbosity -> ConfiguredProgram -> [ProgArg] -> IO ()

rawSystemProgramStdout :: Verbosity -> ConfiguredProgram -> [ProgArg] -> IO String

builtinPrograms :: [Program]

data ProgramConfiguration

emptyProgramConfiguration :: ProgramConfiguration

defaultProgramConfiguration :: ProgramConfiguration

restoreProgramConfiguration :: [Program] -> ProgramConfiguration -> ProgramConfiguration

addKnownProgram :: Program -> ProgramConfiguration -> ProgramConfiguration

addKnownPrograms :: [Program] -> ProgramConfiguration -> ProgramConfiguration

lookupKnownProgram :: String -> ProgramConfiguration -> Maybe Program

knownPrograms :: ProgramConfiguration -> [(Program, Maybe ConfiguredProgram)]

userSpecifyPath :: String -> FilePath -> ProgramConfiguration -> ProgramConfiguration

userSpecifyPaths :: [(String, FilePath)] -> ProgramConfiguration -> ProgramConfiguration

userMaybeSpecifyPath :: String -> Maybe FilePath -> ProgramConfiguration -> ProgramConfiguration

userSpecifyArgs :: String -> [ProgArg] -> ProgramConfiguration -> ProgramConfiguration

userSpecifyArgss :: [(String, [ProgArg])] -> ProgramConfiguration -> ProgramConfiguration

userSpecifiedArgs :: Program -> ProgramConfiguration -> [ProgArg]

lookupProgram :: Program -> ProgramConfiguration -> Maybe ConfiguredProgram

updateProgram :: ConfiguredProgram -> ProgramConfiguration -> ProgramConfiguration

configureProgram :: Verbosity -> Program -> ProgramConfiguration -> IO ProgramConfiguration

configureAllKnownPrograms :: Verbosity -> ProgramConfiguration -> IO ProgramConfiguration

reconfigurePrograms :: Verbosity -> [(String, FilePath)] -> [(String, [ProgArg])] -> ProgramConfiguration -> IO ProgramConfiguration

requireProgram :: Verbosity -> Program -> VersionRange -> ProgramConfiguration -> IO (ConfiguredProgram, ProgramConfiguration)

rawSystemProgramConf :: Verbosity -> Program -> ProgramConfiguration -> [ProgArg] -> IO ()

rawSystemProgramStdoutConf :: Verbosity -> Program -> ProgramConfiguration -> [ProgArg] -> IO String

ghcProgram :: Program

ghcPkgProgram :: Program

nhcProgram :: Program

hmakeProgram :: Program

jhcProgram :: Program

hugsProgram :: Program

ffihugsProgram :: Program

gccProgram :: Program

ranlibProgram :: Program

arProgram :: Program

stripProgram :: Program

happyProgram :: Program

alexProgram :: Program

hsc2hsProgram :: Program

c2hsProgram :: Program

cpphsProgram :: Program

hscolourProgram :: Program

haddockProgram :: Program

greencardProgram :: Program

ldProgram :: Program

tarProgram :: Program

cppProgram :: Program

pkgConfigProgram :: Program

Program and functions for constructing them

data Program

Represents a program which can be configured.

Constructors

Program

programName :: String	The simple name of the program, eg. ghc
programFindLocation :: Verbosity -> IO (Maybe FilePath)	A function to search for the program if it's location was not specified by the user. Usually this will just be a
programFindVersion :: Verbosity -> FilePath -> IO (Maybe Version)	Try to find the version of the program. For many programs this is not possible or is not necessary so it's ok to return Nothing.
programPostConf :: Verbosity -> ConfiguredProgram -> IO [ProgArg]	A function to do any additional configuration after we have located the program (and perhaps identified its version). It is allowed to return additional flags that will be passed to the program on every invocation.

simpleProgram :: String -> Program

Make a simple named program.

By default we'll just search for it in the path and not try to find the version name. You can override these behaviours if necessary, eg:

 simpleProgram "foo" { programFindLocation = ... , programFindVersion ... }

findProgramOnPath :: FilePath -> Verbosity -> IO (Maybe FilePath)

Look for a program on the path.

findProgramVersion

:: ProgArg	version args
-> String -> String	function to select version number from program output
-> Verbosity
-> FilePath	location
-> IO (Maybe Version)
Look for a program and try to find it's version number. It can accept either an absolute path or the name of a program binary, in which case we will look for the program on the path.

Configured program and related functions

data ConfiguredProgram

Constructors

ConfiguredProgram

programId :: String	Just the name again
programVersion :: Maybe Version	The version of this program, if it is known.
programArgs :: [ProgArg]	Default command-line args for this program. These flags will appear first on the command line, so they can be overridden by subsequent flags.
programLocation :: ProgramLocation	Location of the program. eg. `/usr/bin/ghc-6.4`

show/hide

Instances

Eq ConfiguredProgram

Read ConfiguredProgram

Show ConfiguredProgram

programPath :: ConfiguredProgram -> FilePath

The full path of a configured program.

type ProgArg = String

data ProgramLocation

Where a program was found. Also tells us whether it's specifed by user or not. This includes not just the path, but the program as well.

Constructors

UserSpecified

The user gave the path to this program, eg. --ghc-path=/usr/bin/ghc-6.6

locationPath :: FilePath

FoundOnSystem

The location of the program, as located by searching PATH.

locationPath :: FilePath

show/hide

Instances

Eq ProgramLocation

Read ProgramLocation

Show ProgramLocation

rawSystemProgram

:: Verbosity	Verbosity
-> ConfiguredProgram	The program to run
-> [ProgArg]	Any extra arguments to add
-> IO ()
Runs the given configured program.

rawSystemProgramStdout

:: Verbosity	Verbosity
-> ConfiguredProgram	The program to run
-> [ProgArg]	Any extra arguments to add
-> IO String
Runs the given configured program and gets the output.

The collection of unconfigured and configured progams

builtinPrograms :: [Program]

The default list of programs. These programs are typically used internally to Cabal.

The collection of configured programs we can run

data ProgramConfiguration

The configuration is a collection of information about programs. It contains information both about configured programs and also about programs that we are yet to configure.

The idea is that we start from a collection of unconfigured programs and one by one we try to configure them at which point we move them into the configured collection. For unconfigured programs we record not just the Program but also any user-provided arguments and location for the program.

show/hide

Instances

Read ProgramConfiguration

Show ProgramConfiguration

emptyProgramConfiguration :: ProgramConfiguration

defaultProgramConfiguration :: ProgramConfiguration

restoreProgramConfiguration :: [Program] -> ProgramConfiguration -> ProgramConfiguration

The Read/Show instance does not preserve all the unconfigured Programs because Program is not in Read/Show because it contains functions. So to fully restore a deserialised ProgramConfiguration use this function to add back all the known Programs.

It does not add the default programs, but you probably want them, use builtinPrograms in addition to any extra you might need.

addKnownProgram :: Program -> ProgramConfiguration -> ProgramConfiguration

Add a known program that we may configure later

addKnownPrograms :: [Program] -> ProgramConfiguration -> ProgramConfiguration

lookupKnownProgram :: String -> ProgramConfiguration -> Maybe Program

knownPrograms :: ProgramConfiguration -> [(Program, Maybe ConfiguredProgram)]

userSpecifyPath

:: String	Program name
-> FilePath	user-specified path to the program
-> ProgramConfiguration
-> ProgramConfiguration
User-specify this path. Basically override any path information for this program in the configuration. If it's not a known program ignore it.

userSpecifyPaths :: [(String, FilePath)] -> ProgramConfiguration -> ProgramConfiguration

Like userSpecifyPath but for a list of progs and their paths.

userMaybeSpecifyPath :: String -> Maybe FilePath -> ProgramConfiguration -> ProgramConfiguration

userSpecifyArgs

:: String	Program name
-> [ProgArg]	user-specified args
-> ProgramConfiguration
-> ProgramConfiguration
User-specify the arguments for this program. Basically override any args information for this program in the configuration. If it's not a known program, ignore it..

userSpecifyArgss :: [(String, [ProgArg])] -> ProgramConfiguration -> ProgramConfiguration

Like userSpecifyPath but for a list of progs and their args.

userSpecifiedArgs :: Program -> ProgramConfiguration -> [ProgArg]

Get any extra args that have been previously specified for a program.

lookupProgram :: Program -> ProgramConfiguration -> Maybe ConfiguredProgram

Try to find a configured program

updateProgram :: ConfiguredProgram -> ProgramConfiguration -> ProgramConfiguration

Update a configured program in the database.

configureProgram :: Verbosity -> Program -> ProgramConfiguration -> IO ProgramConfiguration

Try to configure a specific program. If the program is already included in the colleciton of unconfigured programs then we use any user-supplied location and arguments. If the program gets configured sucessfully it gets added to the configured collection.

Note that it is not a failure if the program cannot be configured. It's only a failure if the user supplied a location and the program could not be found at that location.

The reason for it not being a failure at this stage is that we don't know up front all the programs we will need, so we try to configure them all. To verify that a program was actually sucessfully configured use requireProgram.

configureAllKnownPrograms :: Verbosity -> ProgramConfiguration -> IO ProgramConfiguration

Try to configure all the known programs that have not yet been configured.

reconfigurePrograms :: Verbosity -> [(String, FilePath)] -> [(String, [ProgArg])] -> ProgramConfiguration -> IO ProgramConfiguration

reconfigure a bunch of programs given new user-specified args. It takes the same inputs as userSpecifyPath and userSpecifyArgs and for all progs with a new path it calls configureProgram.

requireProgram :: Verbosity -> Program -> VersionRange -> ProgramConfiguration -> IO (ConfiguredProgram, ProgramConfiguration)

Check that a program is configured and available to be run.

Additionally check that the version of the program number is suitable. For example AnyVersion or orLaterVersion (Version [1,0] [])

It raises an exception if the program could not be configured or the version is unsuitable, otherwise it returns the configured program.

rawSystemProgramConf

:: Verbosity	verbosity
-> Program	The program to run
-> ProgramConfiguration	look up the program here
-> [ProgArg]	Any extra arguments to add
-> IO ()
Looks up the given program in the program configuration and runs it.

rawSystemProgramStdoutConf

:: Verbosity	verbosity
-> Program	The program to run
-> ProgramConfiguration	look up the program here
-> [ProgArg]	Any extra arguments to add
-> IO String
Looks up the given program in the program configuration and runs it.

Programs that Cabal knows about

ghcProgram :: Program

ghcPkgProgram :: Program

nhcProgram :: Program

hmakeProgram :: Program

jhcProgram :: Program

hugsProgram :: Program

ffihugsProgram :: Program

gccProgram :: Program

ranlibProgram :: Program

arProgram :: Program

stripProgram :: Program

happyProgram :: Program

alexProgram :: Program

hsc2hsProgram :: Program

c2hsProgram :: Program

cpphsProgram :: Program

hscolourProgram :: Program

haddockProgram :: Program

greencardProgram :: Program

ldProgram :: Program

tarProgram :: Program

cppProgram :: Program

pkgConfigProgram :: Program

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