| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Turtle
Contents
Description
See Turtle.Tutorial to learn how to use this library or Turtle.Prelude for a quick-start guide.
Here is the recommended way to import this library:
{-# LANGUAGE OverloadedStrings #-}
import Turtle
import Prelude hiding (FilePath)This module re-exports the rest of the library and also re-exports useful
modules from base:
Turtle.Format provides type-safe string formatting
Turtle.Pattern provides Patterns, which are like more powerful regular
expressions
Turtle.Shell provides a Shell abstraction for building streaming,
exception-safe pipelines
Turtle.Prelude provides a library of Unix-like utilities to get you started with basic shell-like programming within Haskell
Control.Applicative provides two classes:
Applicative, which works withFold,Pattern,Managed, andShellAlternative, which works withPatternandShell
Control.Monad provides two classes:
Control.Monad.IO.Class provides one class:
Data.Monoid provides one class:
Control.Monad.Managed.Safe provides Managed resources
Filesystem.Path.CurrentOS provides FilePath-manipulation utilities
Additionally, you might also want to import the following modules qualified:
- Options.Applicative from
optparse-applicativefor command-line option parsing - Control.Foldl (for predefined folds)
- Control.Foldl.Text (for
Text-specific folds) - Data.Text (for
Text-manipulation utilities) - Data.Text.IO (for reading and writing
Text) - Filesystem.Path.CurrentOS (for the remaining
FilePathutilities)
- module Turtle.Format
- module Turtle.Pattern
- module Turtle.Options
- module Turtle.Shell
- module Turtle.Prelude
- module Control.Applicative
- module Control.Monad
- module Control.Monad.IO.Class
- module Data.Monoid
- module Control.Monad.Managed
- module Filesystem.Path.CurrentOS
- data Fold a b :: * -> * -> * where
- data FoldM m a b :: (* -> *) -> * -> * -> * where
- data Text :: *
- data UTCTime :: *
- data NominalDiffTime :: *
- data Handle :: *
- data ExitCode :: *
- class IsString a where
- fromString :: String -> a
- (&) :: a -> (a -> b) -> b
Modules
module Turtle.Format
module Turtle.Pattern
module Turtle.Options
module Turtle.Shell
module Turtle.Prelude
module Control.Applicative
module Control.Monad
module Control.Monad.IO.Class
module Data.Monoid
module Control.Monad.Managed
module Filesystem.Path.CurrentOS
data Fold a b :: * -> * -> * where
Efficient representation of a left fold that preserves the fold's step function, initial accumulator, and extraction function
This allows the Applicative instance to assemble derived folds that
traverse the container only once
A 'Fold a b' processes elements of type a and results in a
value of type b.
Instances
| Profunctor Fold | |
| Functor (Fold a) | |
| Applicative (Fold a) | |
| Comonad (Fold a) | |
| Floating b => Floating (Fold a b) | |
| Fractional b => Fractional (Fold a b) | |
| Num b => Num (Fold a b) | |
| Monoid b => Monoid (Fold a b) | |
data FoldM m a b :: (* -> *) -> * -> * -> * where
data Text :: *
A space efficient, packed, unboxed Unicode text type.
data UTCTime :: *
This is the simplest representation of UTC. It consists of the day number, and a time offset from midnight. Note that if a day has a leap second added to it, it will have 86401 seconds.
data NominalDiffTime :: *
This is a length of time, as measured by UTC. Conversion functions will treat it as seconds. It has a precision of 10^-12 s. It ignores leap-seconds, so it's not necessarily a fixed amount of clock time. For instance, 23:00 UTC + 2 hours of NominalDiffTime = 01:00 UTC (+ 1 day), regardless of whether a leap-second intervened.
data Handle :: *
Haskell defines operations to read and write characters from and to files,
represented by values of type Handle. Each value of this type is a
handle: a record used by the Haskell run-time system to manage I/O
with file system objects. A handle has at least the following properties:
- whether it manages input or output or both;
- whether it is open, closed or semi-closed;
- whether the object is seekable;
- whether buffering is disabled, or enabled on a line or block basis;
- a buffer (whose length may be zero).
Most handles will also have a current I/O position indicating where the next
input or output operation will occur. A handle is readable if it
manages only input or both input and output; likewise, it is writable if
it manages only output or both input and output. A handle is open when
first allocated.
Once it is closed it can no longer be used for either input or output,
though an implementation cannot re-use its storage while references
remain to it. Handles are in the Show and Eq classes. The string
produced by showing a handle is system dependent; it should include
enough information to identify the handle for debugging. A handle is
equal according to == only to itself; no attempt
is made to compare the internal state of different handles for equality.
data ExitCode :: *
Defines the exit codes that a program can return.
Constructors
| ExitSuccess | indicates successful termination; |
| ExitFailure Int | 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). |
class IsString a where
Class for string-like datastructures; used by the overloaded string extension (-XOverloadedStrings in GHC).
Methods
fromString :: String -> a
Instances