-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Generic text-editor logic for use with fixed-width fonts.
--   
--   This package contains interfaces and implementations of text-editing
--   idioms that can be wired up to UI libraries to create a text-editor
--   widget.
--   
--   The goal is to provide:
--   
--   <ul>
--   <li>Dynamic line wrapping that preserves the cursor and edit
--   positions.</li>
--   <li>Customizable line-wrapping policies and word-hyphenation
--   policies.</li>
--   <li>Automatic management of a dynamically-sized viewable area.</li>
--   <li>Support for novel character types.</li>
--   </ul>
@package WEditor
@version 0.2.0.0


-- | Features of character sets.
module WEditor.Base.Char

-- | Supporting hyphenation.
class HyphenChar c

-- | The canonical hyphen character.
defaultHyphen :: HyphenChar c => c

-- | Dealing with whitespace characters.
class WhitespaceChar c

-- | Predicate for identifying whitespace characters.
defaultIsWhitespace :: WhitespaceChar c => c -> Bool

-- | Dealing with word characters.
class WhitespaceChar c => WordChar c

-- | Predicate for identifying word characters.
defaultIsWordChar :: WordChar c => c -> Bool
instance WEditor.Base.Char.HyphenChar GHC.Types.Char
instance WEditor.Base.Char.WordChar GHC.Types.Char
instance WEditor.Base.Char.WhitespaceChar GHC.Types.Char


-- | Simple representation of viewable text lines.
module WEditor.Base.Line

-- | Line meant for viewing.
data VisibleLine c b
VisibleLine :: b -> [c] -> VisibleLine c b

-- | The type of line break for this line.
[vlBreak] :: VisibleLine c b -> b

-- | The complete data of the line.
[vlText] :: VisibleLine c b -> [c]
instance (GHC.Show.Show b, GHC.Show.Show c) => GHC.Show.Show (WEditor.Base.Line.VisibleLine c b)
instance (GHC.Classes.Ord b, GHC.Classes.Ord c) => GHC.Classes.Ord (WEditor.Base.Line.VisibleLine c b)
instance (GHC.Classes.Eq b, GHC.Classes.Eq c) => GHC.Classes.Eq (WEditor.Base.Line.VisibleLine c b)


-- | Simple representation of text paragraphs.
module WEditor.Base.Para

-- | Single paragraph that has not been parsed into lines.
data UnparsedPara c
UnparsedPara :: [c] -> UnparsedPara c

-- | The complete and uparsed paragraph data.
[upText] :: UnparsedPara c -> [c]

-- | Create an empty paragraph.
emptyPara :: UnparsedPara c
instance GHC.Show.Show c => GHC.Show.Show (WEditor.Base.Para.UnparsedPara c)
instance GHC.Classes.Ord c => GHC.Classes.Ord (WEditor.Base.Para.UnparsedPara c)
instance GHC.Classes.Eq c => GHC.Classes.Eq (WEditor.Base.Para.UnparsedPara c)


-- | Generic text-editing functionality.
module WEditor.Base.Editor

-- | Actions that modify data.
data EditAction c

-- | Insert a block of characters.
InsertText :: [c] -> EditAction c

-- | Delete a single character.
DeleteText :: EditAction c

-- | Modification direction, relative to the cursor.
data EditDirection

-- | Apply the edit before the cursor.
EditBefore :: EditDirection

-- | Apply the edit after the cursor.
EditAfter :: EditDirection

-- | Any action that updates a <a>FixedFontEditor</a>.
type EditorAction c = forall a. FixedFontEditor a c => a -> a

-- | Actions that change the cursor position without changing data.
data MoveDirection

-- | Move up one line.
MoveUp :: MoveDirection

-- | Move down one line.
MoveDown :: MoveDirection

-- | Move backward one character.
MovePrev :: MoveDirection

-- | Move forward one character.
MoveNext :: MoveDirection

-- | Implementation-defined home operation.
MoveHome :: MoveDirection

-- | Implementation-defined end operation.
MoveEnd :: MoveDirection

-- | Implementation-defined page-up operation.
MovePageUp :: MoveDirection

-- | Implementation-defined page-down operation.
MovePageDown :: MoveDirection

-- | Generic text editor for fixed-width fonts.
class FixedFontEditor a c | a -> c

-- | Apply an edit action.
editText :: FixedFontEditor a c => a -> EditAction c -> EditDirection -> a

-- | Break the current paragraph at the cursor.
breakPara :: FixedFontEditor a c => a -> EditDirection -> a

-- | Apply a cursor movement.
moveCursor :: FixedFontEditor a c => a -> MoveDirection -> a

-- | Get the (row,col) cursor position relative to the viewport.
getCursor :: FixedFontEditor a c => a -> (Int, Int)

-- | Get the absolute (paragraph,char) edit position.
--   
--   The position can be restored after cursor movements by calling
--   <a>setEditPoint</a>; however, calling <a>editText</a> or
--   <a>breakPara</a> invalidates this position.
getEditPoint :: FixedFontEditor a c => a -> (Int, Int)

-- | Set the absolute (paragraph,char) edit position.
setEditPoint :: FixedFontEditor a c => a -> (Int, Int) -> a

-- | Get the number of characters in the current paragraph.
getParaSize :: FixedFontEditor a c => a -> Int

-- | Get the number of paragraphs in the document.
getParaCount :: FixedFontEditor a c => a -> Int

-- | Export the modified data.
exportData :: FixedFontEditor a c => a -> [UnparsedPara c]

-- | Action for normal character insertion.
editorAppendAction :: [c] -> EditorAction c

-- | Action for the Backspace key.
editorBackspaceAction :: EditorAction c

-- | Action for the Delete key.
editorDeleteAction :: EditorAction c

-- | Action for the down-arrow key.
editorDownAction :: EditorAction c

-- | Action for the End key.
editorEndAction :: EditorAction c

-- | Action for the Enter key.
editorEnterAction :: EditorAction c

-- | Action for the Home key.
editorHomeAction :: EditorAction c

-- | Action to insert after the cursor.
editorInsertAction :: [c] -> EditorAction c

-- | Action for the left-arrow key.
editorLeftAction :: EditorAction c

-- | Action for the PageDown key.
editorPageDownAction :: EditorAction c

-- | Action for the PageUp key.
editorPageUpAction :: EditorAction c

-- | Action for the right-arrow key.
editorRightAction :: EditorAction c

-- | Action to set the absolute (paragraph,char) edit position.
editorSetPositionAction :: (Int, Int) -> EditorAction c

-- | Action for the up-arrow key.
editorUpAction :: EditorAction c
instance GHC.Show.Show WEditor.Base.Editor.MoveDirection
instance GHC.Classes.Eq WEditor.Base.Editor.MoveDirection
instance GHC.Show.Show WEditor.Base.Editor.EditDirection
instance GHC.Classes.Eq WEditor.Base.Editor.EditDirection
instance GHC.Show.Show c => GHC.Show.Show (WEditor.Base.Editor.EditAction c)
instance GHC.Classes.Eq c => GHC.Classes.Eq (WEditor.Base.Editor.EditAction c)


-- | Generic line-parsing functionality.
module WEditor.Base.Parser

-- | Line parser for fixed-width fonts.
class FixedFontParser a c | a -> c where {
    
    -- | Type used to differentiate between line-break types.
    type family BreakType a :: *;
}

-- | Change the max line width used for parsing. A width of zero must
--   result in breakLines skipping line breaks.
setLineWidth :: FixedFontParser a c => a -> Int -> a

-- | Break the sequence into lines.
--   
--   The following must hold for all possible inputs to a
--   <a>FixedFontParser</a> <tt>p</tt>:
--   
--   <pre>
--   concat (map vlText (breakLines p line)) == line
--   </pre>
--   
--   Implement <a>renderLine</a> and <a>tweakCursor</a> to make visual
--   adjustments (such as adding hyphens or indentation) if necessary.
breakLines :: FixedFontParser a c => a -> [c] -> [VisibleLine c (BreakType a)]

-- | A place-holder line for empty paragraphs.
emptyLine :: FixedFontParser a c => a -> VisibleLine c (BreakType a)

-- | Render the line for viewing. Implement <a>tweakCursor</a> if
--   <a>renderLine</a> changes the positions of any characters on the line.
renderLine :: FixedFontParser a c => a -> VisibleLine c (BreakType a) -> [c]

-- | Adjust the horizontal cursor position.
tweakCursor :: FixedFontParser a c => a -> VisibleLine c (BreakType a) -> Int -> Int

-- | Split the line to create a paragraph break.
splitLine :: FixedFontParser a c => a -> Int -> VisibleLine c (BreakType a) -> (VisibleLine c (BreakType a), VisibleLine c (BreakType a))


-- | Generic editor-viewport functionality.
module WEditor.Base.Viewer

-- | Generic editor viewport for fixed-width fonts.
class FixedFontViewer a c | a -> c

-- | Set the (width,height) size of the viewport. A width &lt; 0 must
--   disable line wrapping, and a height &lt; 0 must disable vertical
--   bounding.
setViewSize :: FixedFontViewer a c => a -> (Int, Int) -> a

-- | Get the (width,height) size of the viewport.
getViewSize :: FixedFontViewer a c => a -> (Int, Int)

-- | Get the visible lines in the viewport. This does not need to
--   completely fill the viewport area, but it must not exceed it.
getVisible :: FixedFontViewer a c => a -> [[c]]

-- | Apply a view change.
updateView :: FixedFontViewer a c => a -> ViewAction -> a

-- | Actions that modify the view without affecting editing.
data ViewAction

-- | Shift the vertical offset. Negative values shift up.
ShiftVertical :: Int -> ViewAction

-- | Attempt to fill the entire viewport.
FillView :: ViewAction

-- | Any action that updates a <a>FixedFontViewer</a>.
type ViewerAction c = forall a. FixedFontViewer a c => a -> a
viewerFillAction :: ViewerAction c

-- | Action to resize the viewport.
viewerResizeAction :: (Int, Int) -> ViewerAction c

-- | Action to shift the view upward.
viewerShiftUpAction :: Int -> ViewerAction c

-- | Action to shift the view downward.
viewerShiftDownAction :: Int -> ViewerAction c
instance GHC.Show.Show WEditor.Base.Viewer.ViewAction
instance GHC.Classes.Eq WEditor.Base.Viewer.ViewAction


-- | Base module for implementing new editor functionality.
module WEditor.Base


-- | Generic document-editing components.
module WEditor.Document

-- | Generic document editor with a dynamic viewport.
--   
--   This editor bounds vertical view scrolling (see <a>ViewAction</a>) to
--   keep the cursor within view.
data EditingDocument c

-- | Create an editor for a document.
editDocument :: FixedFontParser a c => a -> [UnparsedPara c] -> EditingDocument c

-- | Actions that modify data.
data EditAction c

-- | Insert a block of characters.
InsertText :: [c] -> EditAction c

-- | Delete a single character.
DeleteText :: EditAction c

-- | Modification direction, relative to the cursor.
data EditDirection

-- | Apply the edit before the cursor.
EditBefore :: EditDirection

-- | Apply the edit after the cursor.
EditAfter :: EditDirection

-- | Any action that updates a <a>FixedFontEditor</a>.
type EditorAction c = forall a. FixedFontEditor a c => a -> a

-- | Generic text editor for fixed-width fonts.
class FixedFontEditor a c | a -> c

-- | Apply an edit action.
editText :: FixedFontEditor a c => a -> EditAction c -> EditDirection -> a

-- | Break the current paragraph at the cursor.
breakPara :: FixedFontEditor a c => a -> EditDirection -> a

-- | Apply a cursor movement.
moveCursor :: FixedFontEditor a c => a -> MoveDirection -> a

-- | Get the (row,col) cursor position relative to the viewport.
getCursor :: FixedFontEditor a c => a -> (Int, Int)

-- | Get the absolute (paragraph,char) edit position.
--   
--   The position can be restored after cursor movements by calling
--   <a>setEditPoint</a>; however, calling <a>editText</a> or
--   <a>breakPara</a> invalidates this position.
getEditPoint :: FixedFontEditor a c => a -> (Int, Int)

-- | Set the absolute (paragraph,char) edit position.
setEditPoint :: FixedFontEditor a c => a -> (Int, Int) -> a

-- | Get the number of characters in the current paragraph.
getParaSize :: FixedFontEditor a c => a -> Int

-- | Get the number of paragraphs in the document.
getParaCount :: FixedFontEditor a c => a -> Int

-- | Export the modified data.
exportData :: FixedFontEditor a c => a -> [UnparsedPara c]

-- | Line parser for fixed-width fonts.
class FixedFontParser a c | a -> c

-- | Generic editor viewport for fixed-width fonts.
class FixedFontViewer a c | a -> c

-- | Set the (width,height) size of the viewport. A width &lt; 0 must
--   disable line wrapping, and a height &lt; 0 must disable vertical
--   bounding.
setViewSize :: FixedFontViewer a c => a -> (Int, Int) -> a

-- | Get the (width,height) size of the viewport.
getViewSize :: FixedFontViewer a c => a -> (Int, Int)

-- | Get the visible lines in the viewport. This does not need to
--   completely fill the viewport area, but it must not exceed it.
getVisible :: FixedFontViewer a c => a -> [[c]]

-- | Apply a view change.
updateView :: FixedFontViewer a c => a -> ViewAction -> a

-- | Actions that change the cursor position without changing data.
data MoveDirection

-- | Move up one line.
MoveUp :: MoveDirection

-- | Move down one line.
MoveDown :: MoveDirection

-- | Move backward one character.
MovePrev :: MoveDirection

-- | Move forward one character.
MoveNext :: MoveDirection

-- | Implementation-defined home operation.
MoveHome :: MoveDirection

-- | Implementation-defined end operation.
MoveEnd :: MoveDirection

-- | Implementation-defined page-up operation.
MovePageUp :: MoveDirection

-- | Implementation-defined page-down operation.
MovePageDown :: MoveDirection

-- | Single paragraph that has not been parsed into lines.
data UnparsedPara c
UnparsedPara :: [c] -> UnparsedPara c

-- | The complete and uparsed paragraph data.
[upText] :: UnparsedPara c -> [c]

-- | Any action that updates a <a>FixedFontViewer</a>.
type ViewerAction c = forall a. FixedFontViewer a c => a -> a

-- | Action for normal character insertion.
editorAppendAction :: [c] -> EditorAction c

-- | Action for the Backspace key.
editorBackspaceAction :: EditorAction c

-- | Action for the Delete key.
editorDeleteAction :: EditorAction c

-- | Action for the down-arrow key.
editorDownAction :: EditorAction c

-- | Action for the End key.
editorEndAction :: EditorAction c

-- | Action for the Enter key.
editorEnterAction :: EditorAction c

-- | Action for the Home key.
editorHomeAction :: EditorAction c

-- | Action to insert after the cursor.
editorInsertAction :: [c] -> EditorAction c

-- | Action for the left-arrow key.
editorLeftAction :: EditorAction c

-- | Action for the PageDown key.
editorPageDownAction :: EditorAction c

-- | Action for the PageUp key.
editorPageUpAction :: EditorAction c

-- | Action for the right-arrow key.
editorRightAction :: EditorAction c

-- | Action to set the absolute (paragraph,char) edit position.
editorSetPositionAction :: (Int, Int) -> EditorAction c

-- | Action for the up-arrow key.
editorUpAction :: EditorAction c
viewerFillAction :: ViewerAction c

-- | Action to resize the viewport.
viewerResizeAction :: (Int, Int) -> ViewerAction c

-- | Action to shift the view upward.
viewerShiftUpAction :: Int -> ViewerAction c

-- | Action to shift the view downward.
viewerShiftDownAction :: Int -> ViewerAction c
instance GHC.Show.Show (WEditor.Document.EditingDocument c)
instance WEditor.Base.Viewer.FixedFontViewer (WEditor.Document.EditingDocument c) c
instance WEditor.Base.Editor.FixedFontEditor (WEditor.Document.EditingDocument c) c


-- | Line-wrapping implementations. (See <a>FixedFontParser</a> for custom
--   wrapping.)
module WEditor.LineWrap

-- | Wrapping policy that breaks lines based on words. Use
--   <a>breakWords</a> to construct a new value.
data BreakWords c

-- | Line break type for a single paragraph line.
data LineBreak

-- | Word-splitting operations for use with <a>BreakWords</a>.
class WordSplitter a c | a -> c

-- | Determine where to break a word.
--   
--   <ul>
--   <li>The splitter can refuse to process the word by returning
--   <a>Nothing</a>.</li>
--   <li>The segment sizes must provide space for a hyphen if
--   <a>appendHyphen</a> extends the line.</li>
--   <li>Once the word has been split up by <a>BreakWords</a>, the segments
--   are processed as follows:<ol><li>The last segment is prepended to the
--   next line to be parsed. This means that if the word is not split, it
--   gets deferred to the next line.</li><li>If there are more segments,
--   the first is appended to the current line being parsed.</li><li>All
--   remaining segments are put on separate lines between the current and
--   next lines.</li></ol></li>
--   </ul>
splitWord :: WordSplitter a c => a -> Int -> Int -> [c] -> Maybe [Int]

-- | Predicate for characters that should be treated as a part of a word.
isWordChar :: WordSplitter a c => a -> c -> Bool

-- | Predicate for detecting whitespace between words.
isWhitespace :: WordSplitter a c => a -> c -> Bool

-- | Append the canonical hyphen character to show word breaks.
appendHyphen :: WordSplitter a c => a -> [c] -> [c]

-- | Wrapping policy that breaks at exactly the viewer width.
breakExact :: BreakWords c

-- | Wrapping policy that breaks lines based on words.
breakWords :: (Show a, WordSplitter a c) => a -> BreakWords c

-- | Hyphenates words using simple aesthetics, without dictionary
--   awareness.
lazyHyphen :: (WordChar c, HyphenChar c) => LazyHyphen c

-- | The line is at the end of the paragraph.
lineBreakEnd :: LineBreak

-- | The line ends with a hyphenated word.
lineBreakHyphen :: LineBreak

-- | The line is nothing special.
lineBreakSimple :: LineBreak

-- | Avoids splitting words unless they are longer than a single line.
noHyphen :: WordChar c => NoHyphen c
instance GHC.Show.Show (WEditor.LineWrap.LazyHyphen c)
instance GHC.Show.Show (WEditor.LineWrap.NoHyphen c)
instance GHC.Show.Show (WEditor.LineWrap.NoSplit c)
instance GHC.Classes.Ord WEditor.LineWrap.LineBreak
instance GHC.Classes.Eq WEditor.LineWrap.LineBreak
instance (WEditor.Base.Char.WordChar c, WEditor.Base.Char.HyphenChar c) => WEditor.LineWrap.WordSplitter (WEditor.LineWrap.LazyHyphen c) c
instance WEditor.Base.Char.WordChar c => WEditor.LineWrap.WordSplitter (WEditor.LineWrap.NoHyphen c) c
instance GHC.Show.Show (WEditor.LineWrap.BreakWords c)
instance WEditor.Base.Parser.FixedFontParser (WEditor.LineWrap.BreakWords c) c
instance WEditor.LineWrap.WordSplitter (WEditor.LineWrap.NoSplit c) c
instance GHC.Show.Show WEditor.LineWrap.LineBreak