System.IO.CodePage

code-page-0.2.1: Windows code page library for Haskell

Copyright | (C) 2016-2017 Ryan Scott
License | BSD-style (see the file LICENSE)
Maintainer | Ryan Scott
Stability | Provisional
Portability | Portable
Safe Haskell | Safe-Inferred
Language | Haskell2010

System.IO.CodePage

Contents

- Adjusting `CodePage`s
- Notable `CodePage`s
- `Options`
  - Record fields of `Options`
  - `NonWindowsBehavior`
  - Constructing `NonWindowsBehavior`

Description

Exports functions which adjust code pages on Windows, and do nothing on other operating systems.

Synopsis

- withCP65001 :: IO a -> IO a
- withCP1200 :: IO a -> IO a
- withCP1201 :: IO a -> IO a
- withCP12000 :: IO a -> IO a
- withCP12001 :: IO a -> IO a
- withCP1252 :: IO a -> IO a
- withCodePage :: CodePage -> IO a -> IO a
- withCodePageOptions :: Options -> CodePage -> IO a -> IO a
- type CodePage = Word32
- cp65001 :: CodePage
- cp1200 :: CodePage
- cp1201 :: CodePage
- cp12000 :: CodePage
- cp12001 :: CodePage
- cp1252 :: CodePage
- data Options
- defaultOptions :: Options
- chatty :: Options -> Bool
- nonWindowsBehavior :: Options -> NonWindowsBehavior
- data NonWindowsBehavior
- nonWindowsDoNothing :: NonWindowsBehavior
- nonWindowsFallbackCodePageEncoding :: (CodePage -> TextEncoding) -> NonWindowsBehavior
- defaultFallbackCodePageEncoding :: CodePage -> TextEncoding

# Adjusting `CodePage`s

withCP65001 :: IO a -> IO a #

Sets the code page for an action to UTF-8 as necessary.

withCP1200 :: IO a -> IO a #

Sets the code page for an action to UTF-16LE as necessary.

withCP1201 :: IO a -> IO a #

Sets the code page for an action to UTF-16BE as necessary.

withCP12000 :: IO a -> IO a #

Sets the code page for an action to UTF-32LE as necessary.

withCP12001 :: IO a -> IO a #

Sets the code page for an action to UTF-32BE as necessary.

withCP1252 :: IO a -> IO a #

Sets the code page for an action to Latin1 as necessary.

withCodePage :: CodePage -> IO a -> IO a #

Sets the code page for an action as necessary.

On operating systems besides Windows, this will make an effort to change the current `TextEncoding` to something that is equivalent to the supplied `CodePage`. Currently, the only supported `CodePage`s on non-Windows OSes are `cp65001`, `cp1200`, `cp1201`, `cp12000`, and `cp12001`. Supplying any other `CodePage` will result in a runtime error on non-Windows OSes. (If you would like to configure this behavior, use `withCodePageOptions` instead.)

withCodePageOptions :: Options -> CodePage -> IO a -> IO a #

Sets the code page for an action as necessary. If the `Bool` argument is `True`, this function will emit a warning to `stderr` indicating that the code page has been changed. (`withCodePage` sets this argument to `False`.)

# Notable `CodePage`s

type CodePage = Word32 #

A numeric type representing Windows code pages.

cp65001 :: CodePage #

The UTF-8 code page.

cp1200 :: CodePage #

The UTF-16LE code page.

cp1201 :: CodePage #

The UTF-16BE code page.

cp12000 :: CodePage #

The UTF-32LE code page.

cp12001 :: CodePage #

The UTF-32BE code page.

cp1252 :: CodePage #

The Latin1 code page.

# `Options`

data Options #

Options that specify how `withCodePage` and friends should work.

defaultOptions :: Options #

The default `Options`:

    Options
    { chatty = False
    , nonWindowsBehavior =
        nonWindowsFallbackCodePageEncoding defaultFallbackCodePageEncoding
    }

## Record fields of `Options`

chatty :: Options -> Bool #

If `True`, emit a warning to `stderr` indicating that the code page has been changed. If `False`, don't emit any warnings.

nonWindowsBehavior :: Options -> NonWindowsBehavior #

Configures how `withCodePage` and friends should work on non-Windows operating systems.

## `NonWindowsBehavior`

data NonWindowsBehavior #

Specifies how `withCodePage` and friends should work on operating systems other than Windows.

## Constructing `NonWindowsBehavior`

nonWindowsDoNothing :: NonWindowsBehavior #

Don't do anything at all on non-Windows OSes.

nonWindowsFallbackCodePageEncoding :: (CodePage -> TextEncoding) -> NonWindowsBehavior #

On non-Windows OSes, change the `TextEncoding` by converting the `CodePage` argument to a `TextEncoding` using the supplied function.

defaultFallbackCodePageEncoding :: CodePage -> TextEncoding #

Provides a best-effort attempt to convert a `CodePage` to a `TextEncoding` on non-Windows OSes. Errors if given a `CodePage` that it doesn't know how to convert.