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-- GIMP Toolkit (GTK) - text layout functions: Font Descriptions
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-- Created: 8 Feburary 2003
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-- Version $Revision: 1.9 $ from $Date: 2005/10/17 23:06:11 $
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-- Copyright (C) 1999-2005 Axel Simon
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-- This library is free software; you can redistribute it and/or
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-- modify it under the terms of the GNU Lesser General Public
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-- License as published by the Free Software Foundation; either
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-- version 2.1 of the License, or (at your option) any later version.
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-- This library is distributed in the hope that it will be useful,
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-- but WITHOUT ANY WARRANTY; without even the implied warranty of
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-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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-- Lesser General Public License for more details.
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-- Maintainer : gtk2hs-users@lists.sourceforge.net
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-- Stability : provisional
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-- Portability : portable (depends on GHC)
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-- Functions to manage font descriptions.
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-- * Font descriptions provide a way to query and state requirements on
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-- fonts. This data structure has several fields describing different
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-- characteristics of a font. Each of these fields can be set of left
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module Graphics.UI.Gtk.Pango.Description (
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fontDescriptionSetFamily,
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fontDescriptionGetFamily,
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fontDescriptionSetStyle,
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fontDescriptionGetStyle,
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fontDescriptionSetVariant,
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fontDescriptionGetVariant,
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fontDescriptionSetWeight,
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fontDescriptionGetWeight,
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fontDescriptionSetStretch,
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fontDescriptionGetStretch,
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fontDescriptionSetSize,
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fontDescriptionGetSize,
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fontDescriptionUnsetFields,
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fontDescriptionBetterMatch,
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fontDescriptionFromString,
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fontDescriptionToString
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import Data.Bits ((.&.))
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import System.Glib.FFI
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import System.Glib.Flags (Flags, fromFlags)
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import System.Glib.UTFString
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{#import Graphics.UI.Gtk.Types#}
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import System.Glib.GObject (makeNewGObject)
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{#import Graphics.UI.Gtk.Pango.Types#}
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import Graphics.UI.Gtk.Pango.Enums
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import Graphics.UI.Gtk.General.Enums
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import Graphics.UI.Gtk.General.Structs (pangoScale)
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{# context lib="pango" prefix="pango_font_description" #}
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-- | Create a new font description.
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-- * All field are unset.
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fontDescriptionNew :: IO FontDescription
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fontDescriptionNew = {#call unsafe new#} >>= makeNewFontDescription
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-- | Make a deep copy of a font description.
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fontDescriptionCopy :: FontDescription -> IO FontDescription
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fontDescriptionCopy fd = {#call unsafe copy#} fd >>= makeNewFontDescription
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-- | Set the font famliy.
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-- * A font family is a name designating the design of the font (e.g. Sans
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-- or Times) without the variant.
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-- * In some contexts a comma separated list of font families can be used.
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fontDescriptionSetFamily :: FontDescription -> String -> IO ()
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fontDescriptionSetFamily fd family = withUTFString family $ \strPtr ->
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{#call unsafe set_family_static#} fd strPtr
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-- | Get the font family.
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-- * 'Nothing' is returned if the font family is not set.
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fontDescriptionGetFamily :: FontDescription -> IO (Maybe String)
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fontDescriptionGetFamily fd = do
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strPtr <- {#call unsafe get_family#} fd
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if strPtr==nullPtr then return Nothing else
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liftM Just $ peekUTFString strPtr
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-- | Flags denoting which fields in a font description are set.
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{#enum PangoFontMask as FontMask {underscoreToCase} deriving(Bounded) #}
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instance Flags FontMask
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-- | Set the style field.
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-- * Most fonts will have either a 'StyleItalic' or 'StyleOblique'
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fontDescriptionSetStyle :: FontDescription -> FontStyle -> IO ()
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fontDescriptionSetStyle fd p =
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{#call unsafe set_style#} fd (fromIntegral (fromEnum p))
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-- | Get the style field.
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fontDescriptionGetStyle :: FontDescription -> IO (Maybe FontStyle)
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fontDescriptionGetStyle fd = do
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fields <- {#call unsafe get_set_fields#} fd
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if (fromEnum PangoFontMaskStyle) .&. (fromIntegral fields) /=0
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then liftM (Just . toEnum . fromIntegral) $
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{#call unsafe get_style#} fd
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-- | Set the variant field.
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fontDescriptionSetVariant :: FontDescription -> Variant -> IO ()
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fontDescriptionSetVariant fd p =
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{#call unsafe set_variant#} fd (fromIntegral (fromEnum p))
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-- | Get the variant field.
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fontDescriptionGetVariant :: FontDescription -> IO (Maybe Variant)
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fontDescriptionGetVariant fd = do
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fields <- {#call unsafe get_set_fields#} fd
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if (fromEnum PangoFontMaskVariant) .&. (fromIntegral fields) /=0
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then liftM (Just . toEnum . fromIntegral) $
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{#call unsafe get_variant#} fd
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-- | Set the weight field.
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fontDescriptionSetWeight :: FontDescription -> Weight -> IO ()
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fontDescriptionSetWeight fd p =
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{#call unsafe set_weight#} fd (fromIntegral (fromEnum p))
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-- | Get the weight field.
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fontDescriptionGetWeight :: FontDescription -> IO (Maybe Weight)
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fontDescriptionGetWeight fd = do
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fields <- {#call unsafe get_set_fields#} fd
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if (fromEnum PangoFontMaskWeight) .&. (fromIntegral fields) /=0
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then liftM (Just . toEnum . fromIntegral) $
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{#call unsafe get_weight#} fd
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-- | Set the stretch field.
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fontDescriptionSetStretch :: FontDescription -> Stretch -> IO ()
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fontDescriptionSetStretch fd p =
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{#call unsafe set_stretch#} fd (fromIntegral (fromEnum p))
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-- | Get the stretch field.
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fontDescriptionGetStretch :: FontDescription -> IO (Maybe Stretch)
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fontDescriptionGetStretch fd = do
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fields <- {#call unsafe get_set_fields#} fd
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if (fromEnum PangoFontMaskStretch) .&. (fromIntegral fields) /=0
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then liftM (Just . toEnum . fromIntegral) $
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{#call unsafe get_stretch#} fd
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-- | Set the size field.
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-- * The given size is in points (pts). One point is 1\/72 inch.
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fontDescriptionSetSize :: FontDescription -> PangoUnit -> IO ()
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fontDescriptionSetSize fd p =
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{#call unsafe set_size#} fd (puToInt p)
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-- | Get the size field.
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fontDescriptionGetSize :: FontDescription -> IO (Maybe PangoUnit)
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fontDescriptionGetSize fd = do
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fields <- {#call unsafe get_set_fields#} fd
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if (fromEnum PangoFontMaskSize) .&. (fromIntegral fields) /=0
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then liftM (\x -> Just (intToPu x)) $
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{#call unsafe get_size#} fd
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-- | Reset fields in a font description.
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fontDescriptionUnsetFields :: FontDescription -> [FontMask] -> IO ()
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fontDescriptionUnsetFields fd mask =
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{#call unsafe unset_fields#} fd (fromIntegral (fromFlags mask))
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-- | Merge two font descriptions.
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-- * Copy fields from the second description to the first. If the boolean
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-- parameter is set, existing fields in the first description will be
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fontDescriptionMerge :: FontDescription -> FontDescription -> Bool -> IO ()
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fontDescriptionMerge fd1 fd2 replace =
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{#call unsafe merge#} fd1 fd2 (fromBool replace)
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-- | Determine if two descriptions are simliar.
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-- * Returns 'True' if the two descriptions only differ in weight or style.
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fontDescriptionIsMatch :: FontDescription -> FontDescription -> Bool
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fontDescriptionIsMatch fdA fdB = unsafePerformIO $ liftM toBool $
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{#call unsafe better_match#} fdA (FontDescription nullForeignPtr) fdB
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-- | Determine which of two descriptions matches a given description better.
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-- * Returns @True@ if the last description is a better match to the first
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-- arguement than the middle one.
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-- * Approximate matching is done on weight and style. If the other
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-- attributes do not match, the function returns @False@.
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fontDescriptionBetterMatch :: FontDescription -> FontDescription ->
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FontDescription -> Bool
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fontDescriptionBetterMatch fd fdA fdB = unsafePerformIO $ liftM toBool $
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{#call unsafe better_match#} fd fdA fdB
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-- | Create a font description from a string.
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-- * The given argument must have the form
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-- @[FAMILY-LIST] [STYLE-OPTIONS] [SIZE]@ where @FAMILY_LIST@ is a comma
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-- separated list of font families optionally terminated by a comma,
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-- @STYLE_OPTIONS@ is a whitespace separated list of words where each
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-- word describes one of style, variant, weight or stretch. @SIZE@ is
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-- a decimal number giving the size of the font in points. If any of
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-- these fields is absent, the resulting 'FontDescription' will have
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-- the corresponing fields unset.
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fontDescriptionFromString :: String -> IO FontDescription
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fontDescriptionFromString descr = withUTFString descr $ \strPtr ->
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{#call unsafe from_string#} strPtr >>= makeNewFontDescription
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-- | Convert a font description to a string.
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-- * Creates a string representation of a font description. See
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-- 'fontDescriptionFromString' for the format of the string.
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fontDescriptionToString :: FontDescription -> IO String
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fontDescriptionToString fd = do
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strPtr <- {#call unsafe to_string#} fd
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str <- peekUTFString strPtr
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{#call unsafe g_free#} (castPtr strPtr)
added
removed
gtk/Graphics/UI/Gtk/Pango/Description.chs
