System.PlanB.Type

Types and type classes for “Plan B” library. You usually don't need to import this module because System.PlanB already exports everything you need.

Documentation

data Subject

We use this as named kind with two promoted constructors. The constructors are used as phantom types to index PbConfig.

Constructors

New

Existing

data AlreadyExistsBehavior

Custom behavior for cases when something already exists.

Constructors

AebOverride

First delete that object, then do your thing

AebUse

Continue to work with that object instead

Instances

Bounded AlreadyExistsBehavior

Methods

minBound :: AlreadyExistsBehavior

maxBound :: AlreadyExistsBehavior

Enum AlreadyExistsBehavior

Methods

succ :: AlreadyExistsBehavior -> AlreadyExistsBehavior

pred :: AlreadyExistsBehavior -> AlreadyExistsBehavior

toEnum :: Int -> AlreadyExistsBehavior

fromEnum :: AlreadyExistsBehavior -> Int

enumFrom :: AlreadyExistsBehavior -> [AlreadyExistsBehavior]

enumFromThen :: AlreadyExistsBehavior -> AlreadyExistsBehavior -> [AlreadyExistsBehavior]

enumFromTo :: AlreadyExistsBehavior -> AlreadyExistsBehavior -> [AlreadyExistsBehavior]

enumFromThenTo :: AlreadyExistsBehavior -> AlreadyExistsBehavior -> AlreadyExistsBehavior -> [AlreadyExistsBehavior]

Eq AlreadyExistsBehavior

Methods

(==) :: AlreadyExistsBehavior -> AlreadyExistsBehavior -> Bool

(/=) :: AlreadyExistsBehavior -> AlreadyExistsBehavior -> Bool

data PbConfig :: Subject -> *

The configuration allows to control behavior of the library in details. It's a Monoid and so various configuration settings can be combined using mappend while mempty represents default behavior.

When combining conflicting configuration settings, the value on the left side of mappend wins:

overrideIfExists <> useIfExists -- will override

Instances

Monoid (PbConfig k)

Methods

mempty :: PbConfig k

mappend :: PbConfig k -> PbConfig k -> PbConfig k

mconcat :: [PbConfig k] -> PbConfig k

CanHandleExisting (PbConfig New)

Methods

overrideIfExists :: PbConfig New

useIfExists :: PbConfig New

howHandleExisting :: PbConfig New -> Maybe AlreadyExistsBehavior

HasTemp (PbConfig k)

Methods

tempDir :: Path Abs Dir -> PbConfig k

nameTemplate :: String -> PbConfig k

preserveCorpse :: PbConfig k

getTempDir :: PbConfig k -> Maybe (Path Abs Dir)

getNameTemplate :: PbConfig k -> Maybe String

getPreserveCorpse :: PbConfig k -> Bool

class HasTemp c where

The type class is for data types that include information specifying how to create temporary files and directories and whether to delete them automatically or not.

Minimal complete definition

tempDir, nameTemplate, preserveCorpse, getTempDir, getNameTemplate, getPreserveCorpse

Methods

tempDir :: Path Abs Dir -> c

Specifies name of temporary directory to use. Default is the system temporary directory. If the directory does not exist, it will be created, but not deleted.

nameTemplate :: String -> c

Specify template to use to name temporary directory, see openTempFile, default is "plan-b".

preserveCorpse :: c

preserveCorpse preserves temporary files and directories when exception is thrown (normally they are removed).

getTempDir :: c -> Maybe (Path Abs Dir)

getNameTemplate :: c -> Maybe String

getPreserveCorpse :: c -> Bool

Instances

HasTemp (PbConfig k)

Methods

tempDir :: Path Abs Dir -> PbConfig k

nameTemplate :: String -> PbConfig k

preserveCorpse :: PbConfig k

getTempDir :: PbConfig k -> Maybe (Path Abs Dir)

getNameTemplate :: PbConfig k -> Maybe String

getPreserveCorpse :: PbConfig k -> Bool

class CanHandleExisting c where

The type class includes data types that contain information about what to do when some object already exists. There are two scenarios currently supported: override it or use it.

Minimal complete definition

overrideIfExists, useIfExists, howHandleExisting

Methods

overrideIfExists :: c

The option allows to avoid throwing exception if upon completion of specified action file with given name already exists in the file system.

useIfExists :: c

The option will copy already existing file into temporary location, so you can edit it instead of creating new file.

howHandleExisting :: c -> Maybe AlreadyExistsBehavior

Instances

CanHandleExisting (PbConfig New)

Methods

overrideIfExists :: PbConfig New

useIfExists :: PbConfig New

howHandleExisting :: PbConfig New -> Maybe AlreadyExistsBehavior