| Copyright | Will Thompson Iñaki García Etxebarria and Jonas Platte | 
|---|---|
| License | LGPL-2.1 | 
| Maintainer | Iñaki García Etxebarria | 
| Safe Haskell | Safe-Inferred | 
| Language | Haskell2010 | 
GI.Gtk.Structs.TextIter
Contents
- Exported types
- Methods- assign
- backwardChar
- backwardChars
- backwardCursorPosition
- backwardCursorPositions
- backwardFindChar
- backwardLine
- backwardLines
- backwardSearch
- backwardSentenceStart
- backwardSentenceStarts
- backwardToTagToggle
- backwardVisibleCursorPosition
- backwardVisibleCursorPositions
- backwardVisibleLine
- backwardVisibleLines
- backwardVisibleWordStart
- backwardVisibleWordStarts
- backwardWordStart
- backwardWordStarts
- canInsert
- compare
- copy
- editable
- endsLine
- endsSentence
- endsTag
- endsWord
- equal
- forwardChar
- forwardChars
- forwardCursorPosition
- forwardCursorPositions
- forwardFindChar
- forwardLine
- forwardLines
- forwardSearch
- forwardSentenceEnd
- forwardSentenceEnds
- forwardToEnd
- forwardToLineEnd
- forwardToTagToggle
- forwardVisibleCursorPosition
- forwardVisibleCursorPositions
- forwardVisibleLine
- forwardVisibleLines
- forwardVisibleWordEnd
- forwardVisibleWordEnds
- forwardWordEnd
- forwardWordEnds
- free
- getBuffer
- getBytesInLine
- getChar
- getCharsInLine
- getChildAnchor
- getLanguage
- getLine
- getLineIndex
- getLineOffset
- getMarks
- getOffset
- getPaintable
- getSlice
- getTags
- getText
- getToggledTags
- getVisibleLineIndex
- getVisibleLineOffset
- getVisibleSlice
- getVisibleText
- hasTag
- inRange
- insideSentence
- insideWord
- isCursorPosition
- isEnd
- isStart
- order
- setLine
- setLineIndex
- setLineOffset
- setOffset
- setVisibleLineIndex
- setVisibleLineOffset
- startsLine
- startsSentence
- startsTag
- startsWord
- togglesTag
 
Description
You may wish to begin by reading the [text widget conceptual overview][TextWidget] which gives an overview of all the objects and data types related to the text widget and how they work together.
Synopsis
- newtype TextIter = TextIter (ManagedPtr TextIter)
- newZeroTextIter :: MonadIO m => m TextIter
- textIterAssign :: (HasCallStack, MonadIO m) => TextIter -> TextIter -> m ()
- textIterBackwardChar :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterBackwardChars :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterBackwardCursorPosition :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterBackwardCursorPositions :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterBackwardFindChar :: (HasCallStack, MonadIO m) => TextIter -> TextCharPredicate -> Maybe TextIter -> m Bool
- textIterBackwardLine :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterBackwardLines :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterBackwardSearch :: (HasCallStack, MonadIO m) => TextIter -> Text -> [TextSearchFlags] -> Maybe TextIter -> m (Bool, TextIter, TextIter)
- textIterBackwardSentenceStart :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterBackwardSentenceStarts :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterBackwardToTagToggle :: (HasCallStack, MonadIO m, IsTextTag a) => TextIter -> Maybe a -> m Bool
- textIterBackwardVisibleCursorPosition :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterBackwardVisibleCursorPositions :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterBackwardVisibleLine :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterBackwardVisibleLines :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterBackwardVisibleWordStart :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterBackwardVisibleWordStarts :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterBackwardWordStart :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterBackwardWordStarts :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterCanInsert :: (HasCallStack, MonadIO m) => TextIter -> Bool -> m Bool
- textIterCompare :: (HasCallStack, MonadIO m) => TextIter -> TextIter -> m Int32
- textIterCopy :: (HasCallStack, MonadIO m) => TextIter -> m TextIter
- textIterEditable :: (HasCallStack, MonadIO m) => TextIter -> Bool -> m Bool
- textIterEndsLine :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterEndsSentence :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterEndsTag :: (HasCallStack, MonadIO m, IsTextTag a) => TextIter -> Maybe a -> m Bool
- textIterEndsWord :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterEqual :: (HasCallStack, MonadIO m) => TextIter -> TextIter -> m Bool
- textIterForwardChar :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterForwardChars :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterForwardCursorPosition :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterForwardCursorPositions :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterForwardFindChar :: (HasCallStack, MonadIO m) => TextIter -> TextCharPredicate -> Maybe TextIter -> m Bool
- textIterForwardLine :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterForwardLines :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterForwardSearch :: (HasCallStack, MonadIO m) => TextIter -> Text -> [TextSearchFlags] -> Maybe TextIter -> m (Bool, TextIter, TextIter)
- textIterForwardSentenceEnd :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterForwardSentenceEnds :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterForwardToEnd :: (HasCallStack, MonadIO m) => TextIter -> m ()
- textIterForwardToLineEnd :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterForwardToTagToggle :: (HasCallStack, MonadIO m, IsTextTag a) => TextIter -> Maybe a -> m Bool
- textIterForwardVisibleCursorPosition :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterForwardVisibleCursorPositions :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterForwardVisibleLine :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterForwardVisibleLines :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterForwardVisibleWordEnd :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterForwardVisibleWordEnds :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterForwardWordEnd :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterForwardWordEnds :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m Bool
- textIterFree :: (HasCallStack, MonadIO m) => TextIter -> m ()
- textIterGetBuffer :: (HasCallStack, MonadIO m) => TextIter -> m TextBuffer
- textIterGetBytesInLine :: (HasCallStack, MonadIO m) => TextIter -> m Int32
- textIterGetChar :: (HasCallStack, MonadIO m) => TextIter -> m Char
- textIterGetCharsInLine :: (HasCallStack, MonadIO m) => TextIter -> m Int32
- textIterGetChildAnchor :: (HasCallStack, MonadIO m) => TextIter -> m TextChildAnchor
- textIterGetLanguage :: (HasCallStack, MonadIO m) => TextIter -> m Language
- textIterGetLine :: (HasCallStack, MonadIO m) => TextIter -> m Int32
- textIterGetLineIndex :: (HasCallStack, MonadIO m) => TextIter -> m Int32
- textIterGetLineOffset :: (HasCallStack, MonadIO m) => TextIter -> m Int32
- textIterGetMarks :: (HasCallStack, MonadIO m) => TextIter -> m [TextMark]
- textIterGetOffset :: (HasCallStack, MonadIO m) => TextIter -> m Int32
- textIterGetPaintable :: (HasCallStack, MonadIO m) => TextIter -> m Paintable
- textIterGetSlice :: (HasCallStack, MonadIO m) => TextIter -> TextIter -> m Text
- textIterGetTags :: (HasCallStack, MonadIO m) => TextIter -> m [TextTag]
- textIterGetText :: (HasCallStack, MonadIO m) => TextIter -> TextIter -> m Text
- textIterGetToggledTags :: (HasCallStack, MonadIO m) => TextIter -> Bool -> m [TextTag]
- textIterGetVisibleLineIndex :: (HasCallStack, MonadIO m) => TextIter -> m Int32
- textIterGetVisibleLineOffset :: (HasCallStack, MonadIO m) => TextIter -> m Int32
- textIterGetVisibleSlice :: (HasCallStack, MonadIO m) => TextIter -> TextIter -> m Text
- textIterGetVisibleText :: (HasCallStack, MonadIO m) => TextIter -> TextIter -> m Text
- textIterHasTag :: (HasCallStack, MonadIO m, IsTextTag a) => TextIter -> a -> m Bool
- textIterInRange :: (HasCallStack, MonadIO m) => TextIter -> TextIter -> TextIter -> m Bool
- textIterInsideSentence :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterInsideWord :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterIsCursorPosition :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterIsEnd :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterIsStart :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterOrder :: (HasCallStack, MonadIO m) => TextIter -> TextIter -> m ()
- textIterSetLine :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m ()
- textIterSetLineIndex :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m ()
- textIterSetLineOffset :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m ()
- textIterSetOffset :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m ()
- textIterSetVisibleLineIndex :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m ()
- textIterSetVisibleLineOffset :: (HasCallStack, MonadIO m) => TextIter -> Int32 -> m ()
- textIterStartsLine :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterStartsSentence :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterStartsTag :: (HasCallStack, MonadIO m, IsTextTag a) => TextIter -> Maybe a -> m Bool
- textIterStartsWord :: (HasCallStack, MonadIO m) => TextIter -> m Bool
- textIterTogglesTag :: (HasCallStack, MonadIO m, IsTextTag a) => TextIter -> Maybe a -> m Bool
Exported types
Memory-managed wrapper type.
Instances
| Eq TextIter Source # | |
| GBoxed TextIter Source # | |
| Defined in GI.Gtk.Structs.TextIter | |
| ManagedPtrNewtype TextIter Source # | |
| Defined in GI.Gtk.Structs.TextIter Methods toManagedPtr :: TextIter -> ManagedPtr TextIter | |
| TypedObject TextIter Source # | |
| Defined in GI.Gtk.Structs.TextIter | |
| HasParentTypes TextIter Source # | |
| Defined in GI.Gtk.Structs.TextIter | |
| tag ~ 'AttrSet => Constructible TextIter tag Source # | |
| IsGValue (Maybe TextIter) Source # | Convert  | 
| Defined in GI.Gtk.Structs.TextIter Methods gvalueGType_ :: IO GType gvalueSet_ :: Ptr GValue -> Maybe TextIter -> IO () gvalueGet_ :: Ptr GValue -> IO (Maybe TextIter) | |
| type ParentTypes TextIter Source # | |
| Defined in GI.Gtk.Structs.TextIter | |
Methods
Click to display all available methods, including inherited ones
Methods
assign, backwardChar, backwardChars, backwardCursorPosition, backwardCursorPositions, backwardFindChar, backwardLine, backwardLines, backwardSearch, backwardSentenceStart, backwardSentenceStarts, backwardToTagToggle, backwardVisibleCursorPosition, backwardVisibleCursorPositions, backwardVisibleLine, backwardVisibleLines, backwardVisibleWordStart, backwardVisibleWordStarts, backwardWordStart, backwardWordStarts, canInsert, compare, copy, editable, endsLine, endsSentence, endsTag, endsWord, equal, forwardChar, forwardChars, forwardCursorPosition, forwardCursorPositions, forwardFindChar, forwardLine, forwardLines, forwardSearch, forwardSentenceEnd, forwardSentenceEnds, forwardToEnd, forwardToLineEnd, forwardToTagToggle, forwardVisibleCursorPosition, forwardVisibleCursorPositions, forwardVisibleLine, forwardVisibleLines, forwardVisibleWordEnd, forwardVisibleWordEnds, forwardWordEnd, forwardWordEnds, free, hasTag, inRange, insideSentence, insideWord, isCursorPosition, isEnd, isStart, order, startsLine, startsSentence, startsTag, startsWord, togglesTag.
Getters
getBuffer, getBytesInLine, getChar, getCharsInLine, getChildAnchor, getLanguage, getLine, getLineIndex, getLineOffset, getMarks, getOffset, getPaintable, getSlice, getTags, getText, getToggledTags, getVisibleLineIndex, getVisibleLineOffset, getVisibleSlice, getVisibleText.
Setters
setLine, setLineIndex, setLineOffset, setOffset, setVisibleLineIndex, setVisibleLineOffset.
assign
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextIter | 
 | 
| -> m () | 
Assigns the value of other to iter.  This function
 is not useful in applications, because iterators can be assigned
 with GtkTextIter i = j;. The
 function is used by language bindings.
backwardChar
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether movement was possible | 
Moves backward by one character offset. Returns True if movement
 was possible; if iter was the first in the buffer (character
 offset 0), textIterBackwardChar returns False for convenience when
 writing loops.
backwardChars
textIterBackwardChars Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns: whether  | 
Moves count characters backward, if possible (if count would move
 past the start or end of the buffer, moves to the start or end of
 the buffer).  The return value indicates whether the iterator moved
 onto a dereferenceable position; if the iterator didn’t move, or
 moved onto the end iterator, then False is returned. If count is 0,
 the function does nothing and returns False.
backwardCursorPosition
textIterBackwardCursorPosition Source #
Like textIterForwardCursorPosition, but moves backward.
backwardCursorPositions
textIterBackwardCursorPositions Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Moves up to count cursor positions. See
 textIterForwardCursorPosition for details.
backwardFindChar
textIterBackwardFindChar Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextCharPredicate | 
 | 
| -> Maybe TextIter | 
 | 
| -> m Bool | Returns: whether a match was found | 
Same as textIterForwardFindChar, but goes backward from iter.
backwardLine
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether  | 
Moves iter to the start of the previous line. Returns True if
 iter could be moved; i.e. if iter was at character offset 0, this
 function returns False. Therefore if iter was already on line 0,
 but not at the start of the line, iter is snapped to the start of
 the line and the function returns True. (Note that this implies that
 in a loop calling this function, the line number may not change on
 every iteration, if your first iteration is on line 0.)
backwardLines
textIterBackwardLines Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns: whether  | 
Moves count lines backward, if possible (if count would move
 past the start or end of the buffer, moves to the start or end of
 the buffer).  The return value indicates whether the iterator moved
 onto a dereferenceable position; if the iterator didn’t move, or
 moved onto the end iterator, then False is returned. If count is 0,
 the function does nothing and returns False. If count is negative,
 moves forward by 0 - count lines.
backwardSearch
textIterBackwardSearch Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Text | 
 | 
| -> [TextSearchFlags] | 
 | 
| -> Maybe TextIter | 
 | 
| -> m (Bool, TextIter, TextIter) | Returns: whether a match was found | 
Same as textIterForwardSearch, but moves backward.
matchEnd will never be set to a TextIter located after iter, even if
 there is a possible matchStart before or at iter.
backwardSentenceStart
textIterBackwardSentenceStart Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves backward to the previous sentence start; if iter is already at
 the start of a sentence, moves backward to the next one.  Sentence
 boundaries are determined by Pango and should be correct for nearly
 any language (if not, the correct fix would be to the Pango text
 boundary algorithms).
backwardSentenceStarts
textIterBackwardSentenceStarts Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Calls textIterBackwardSentenceStart up to count times,
 or until it returns False. If count is negative, moves forward
 instead of backward.
backwardToTagToggle
textIterBackwardToTagToggle Source #
Arguments
| :: (HasCallStack, MonadIO m, IsTextTag a) | |
| => TextIter | 
 | 
| -> Maybe a | |
| -> m Bool | Returns: whether we found a tag toggle before  | 
Moves backward to the next toggle (on or off) of the
 TextTag tag, or to the next toggle of any tag if
 tag is Nothing. If no matching tag toggles are found,
 returns False, otherwise True. Does not return toggles
 located at iter, only toggles before iter. Sets iter
 to the location of the toggle, or the start of the buffer
 if no toggle is found.
backwardVisibleCursorPosition
textIterBackwardVisibleCursorPosition Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves iter forward to the previous visible cursor position. See
 textIterBackwardCursorPosition for details.
backwardVisibleCursorPositions
textIterBackwardVisibleCursorPositions Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Moves up to count visible cursor positions. See
 textIterBackwardCursorPosition for details.
backwardVisibleLine
textIterBackwardVisibleLine Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether  | 
Moves iter to the start of the previous visible line. Returns True if
 iter could be moved; i.e. if iter was at character offset 0, this
 function returns False. Therefore if iter was already on line 0,
 but not at the start of the line, iter is snapped to the start of
 the line and the function returns True. (Note that this implies that
 in a loop calling this function, the line number may not change on
 every iteration, if your first iteration is on line 0.)
backwardVisibleLines
textIterBackwardVisibleLines Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns: whether  | 
Moves count visible lines backward, if possible (if count would move
 past the start or end of the buffer, moves to the start or end of
 the buffer).  The return value indicates whether the iterator moved
 onto a dereferenceable position; if the iterator didn’t move, or
 moved onto the end iterator, then False is returned. If count is 0,
 the function does nothing and returns False. If count is negative,
 moves forward by 0 - count lines.
backwardVisibleWordStart
textIterBackwardVisibleWordStart Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves backward to the previous visible word start. (If iter is currently
 on a word start, moves backward to the next one after that.) Word breaks
 are determined by Pango and should be correct for nearly any
 language (if not, the correct fix would be to the Pango word break
 algorithms).
backwardVisibleWordStarts
textIterBackwardVisibleWordStarts Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Calls textIterBackwardVisibleWordStart up to count times.
backwardWordStart
textIterBackwardWordStart Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves backward to the previous word start. (If iter is currently on a
 word start, moves backward to the next one after that.) Word breaks
 are determined by Pango and should be correct for nearly any
 language (if not, the correct fix would be to the Pango word break
 algorithms).
backwardWordStarts
textIterBackwardWordStarts Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Calls textIterBackwardWordStart up to count times.
canInsert
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Bool | 
 | 
| -> m Bool | Returns: whether text inserted at  | 
Considering the default editability of the buffer, and tags that
 affect editability, determines whether text inserted at iter would
 be editable. If text inserted at iter would be editable then the
 user should be allowed to insert text at iter.
 textBufferInsertInteractive uses this function to decide
 whether insertions are allowed at a given position.
compare
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextIter | 
 | 
| -> m Int32 | Returns: -1 if  | 
A qsort()-style function that returns negative if lhs is less than
 rhs, positive if lhs is greater than rhs, and 0 if they’re equal.
 Ordering is in character offset order, i.e. the first character in the buffer
 is less than the second character in the buffer.
copy
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m TextIter | Returns: a copy of the  | 
Creates a dynamically-allocated copy of an iterator. This function
 is not useful in applications, because iterators can be copied with a
 simple assignment (GtkTextIter i = j;). The
 function is used by language bindings.
editable
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Bool | 
 | 
| -> m Bool | Returns: whether  | 
Returns whether the character at iter is within an editable region
 of text.
Non-editable text is “locked” and can’t be changed by the
 user via TextView. If no tags applied to this text affect
 editability, defaultSetting will be returned.
You don’t want to use this function to decide whether text can be
 inserted at iter, because for insertion you don’t want to know
 whether the char at iter is inside an editable range, you want to
 know whether a new character inserted at iter would be inside an
 editable range. Use textIterCanInsert to handle this
 case.
endsLine
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether  | 
Returns True if iter points to the start of the paragraph
 delimiter characters for a line (delimiters will be either a
 newline, a carriage return, a carriage return followed by a
 newline, or a Unicode paragraph separator character). Note that an
 iterator pointing to the \n of a \r\n pair will not be counted as
 the end of a line, the line ends before the \r. The end iterator is
 considered to be at the end of a line, even though there are no
 paragraph delimiter chars there.
endsSentence
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Determines whether iter ends a sentence.  Sentence boundaries are
 determined by Pango and should be correct for nearly any language
 (if not, the correct fix would be to the Pango text boundary
 algorithms).
endsTag
Arguments
| :: (HasCallStack, MonadIO m, IsTextTag a) | |
| => TextIter | 
 | 
| -> Maybe a | |
| -> m Bool | Returns: whether  | 
Returns True if tag is toggled off at exactly this point. If tag
 is Nothing, returns True if any tag is toggled off at this point.
Note that if textIterEndsTag returns True, it means that iter is
 at the end of the tagged range, but that the character
 at iter is outside the tagged range. In other words,
 unlike textIterStartsTag, if textIterEndsTag returns True,
 textIterHasTag will return False for the same parameters.
endsWord
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Determines whether iter ends a natural-language word.  Word breaks
 are determined by Pango and should be correct for nearly any
 language (if not, the correct fix would be to the Pango word break
 algorithms).
equal
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextIter | 
 | 
| -> m Bool | Returns:  | 
Tests whether two iterators are equal, using the fastest possible
 mechanism. This function is very fast; you can expect it to perform
 better than e.g. getting the character offset for each iterator and
 comparing the offsets yourself. Also, it’s a bit faster than
 textIterCompare.
forwardChar
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether  | 
Moves iter forward by one character offset. Note that images
 embedded in the buffer occupy 1 character slot, so
 textIterForwardChar may actually move onto an image instead
 of a character, if you have images in your buffer.  If iter is the
 end iterator or one character before it, iter will now point at
 the end iterator, and textIterForwardChar returns False for
 convenience when writing loops.
forwardChars
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns: whether  | 
Moves count characters if possible (if count would move past the
 start or end of the buffer, moves to the start or end of the
 buffer). The return value indicates whether the new position of
 iter is different from its original position, and dereferenceable
 (the last iterator in the buffer is not dereferenceable). If count
 is 0, the function does nothing and returns False.
forwardCursorPosition
textIterForwardCursorPosition Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves iter forward by a single cursor position. Cursor positions
 are (unsurprisingly) positions where the cursor can appear. Perhaps
 surprisingly, there may not be a cursor position between all
 characters. The most common example for European languages would be
 a carriage return/newline sequence. For some Unicode characters,
 the equivalent of say the letter “a” with an accent mark will be
 represented as two characters, first the letter then a "combining
 mark" that causes the accent to be rendered; so the cursor can’t go
 between those two characters. See also the LogAttr-struct and
 break function.
forwardCursorPositions
textIterForwardCursorPositions Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Moves up to count cursor positions. See
 textIterForwardCursorPosition for details.
forwardFindChar
textIterForwardFindChar Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextCharPredicate | 
 | 
| -> Maybe TextIter | 
 | 
| -> m Bool | Returns: whether a match was found | 
forwardLine
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether  | 
forwardLines
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns: whether  | 
Moves count lines forward, if possible (if count would move
 past the start or end of the buffer, moves to the start or end of
 the buffer).  The return value indicates whether the iterator moved
 onto a dereferenceable position; if the iterator didn’t move, or
 moved onto the end iterator, then False is returned. If count is 0,
 the function does nothing and returns False. If count is negative,
 moves backward by 0 - count lines.
forwardSearch
textIterForwardSearch Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Text | 
 | 
| -> [TextSearchFlags] | 
 | 
| -> Maybe TextIter | 
 | 
| -> m (Bool, TextIter, TextIter) | Returns: whether a match was found | 
Searches forward for str. Any match is returned by setting
 matchStart to the first character of the match and matchEnd to the
 first character after the match. The search will not continue past
 limit. Note that a search is a linear or O(n) operation, so you
 may wish to use limit to avoid locking up your UI on large
 buffers.
matchStart will never be set to a TextIter located before iter, even if
 there is a possible matchEnd after or at iter.
forwardSentenceEnd
textIterForwardSentenceEnd Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves forward to the next sentence end. (If iter is at the end of
 a sentence, moves to the next end of sentence.)  Sentence
 boundaries are determined by Pango and should be correct for nearly
 any language (if not, the correct fix would be to the Pango text
 boundary algorithms).
forwardSentenceEnds
textIterForwardSentenceEnds Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Calls textIterForwardSentenceEnd count times (or until
 textIterForwardSentenceEnd returns False). If count is
 negative, moves backward instead of forward.
forwardToEnd
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m () | 
Moves iter forward to the “end iterator,” which points one past the last
 valid character in the buffer. textIterGetChar called on the
 end iterator returns 0, which is convenient for writing loops.
forwardToLineEnd
textIterForwardToLineEnd Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves the iterator to point to the paragraph delimiter characters,
 which will be either a newline, a carriage return, a carriage
 return/newline in sequence, or the Unicode paragraph separator
 character. If the iterator is already at the paragraph delimiter
 characters, moves to the paragraph delimiter characters for the
 next line. If iter is on the last line in the buffer, which does
 not end in paragraph delimiters, moves to the end iterator (end of
 the last line), and returns False.
forwardToTagToggle
textIterForwardToTagToggle Source #
Arguments
| :: (HasCallStack, MonadIO m, IsTextTag a) | |
| => TextIter | 
 | 
| -> Maybe a | |
| -> m Bool | Returns: whether we found a tag toggle after  | 
Moves forward to the next toggle (on or off) of the
 TextTag tag, or to the next toggle of any tag if
 tag is Nothing. If no matching tag toggles are found,
 returns False, otherwise True. Does not return toggles
 located at iter, only toggles after iter. Sets iter to
 the location of the toggle, or to the end of the buffer
 if no toggle is found.
forwardVisibleCursorPosition
textIterForwardVisibleCursorPosition Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves iter forward to the next visible cursor position. See
 textIterForwardCursorPosition for details.
forwardVisibleCursorPositions
textIterForwardVisibleCursorPositions Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Moves up to count visible cursor positions. See
 textIterForwardCursorPosition for details.
forwardVisibleLine
textIterForwardVisibleLine Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether  | 
forwardVisibleLines
textIterForwardVisibleLines Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns: whether  | 
Moves count visible lines forward, if possible (if count would move
 past the start or end of the buffer, moves to the start or end of
 the buffer).  The return value indicates whether the iterator moved
 onto a dereferenceable position; if the iterator didn’t move, or
 moved onto the end iterator, then False is returned. If count is 0,
 the function does nothing and returns False. If count is negative,
 moves backward by 0 - count lines.
forwardVisibleWordEnd
textIterForwardVisibleWordEnd Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves forward to the next visible word end. (If iter is currently on a
 word end, moves forward to the next one after that.) Word breaks
 are determined by Pango and should be correct for nearly any
 language (if not, the correct fix would be to the Pango word break
 algorithms).
forwardVisibleWordEnds
textIterForwardVisibleWordEnds Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Calls textIterForwardVisibleWordEnd up to count times.
forwardWordEnd
textIterForwardWordEnd Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Moves forward to the next word end. (If iter is currently on a
 word end, moves forward to the next one after that.) Word breaks
 are determined by Pango and should be correct for nearly any
 language (if not, the correct fix would be to the Pango word break
 algorithms).
forwardWordEnds
textIterForwardWordEnds Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m Bool | Returns:  | 
Calls textIterForwardWordEnd up to count times.
free
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m () | 
Free an iterator allocated on the heap. This function is intended for use in language bindings, and is not especially useful for applications, because iterators can simply be allocated on the stack.
getBuffer
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m TextBuffer | Returns: the buffer | 
Returns the TextBuffer this iterator is associated with.
getBytesInLine
textIterGetBytesInLine Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Int32 | Returns: number of bytes in the line | 
Returns the number of bytes in the line containing iter,
 including the paragraph delimiters.
getChar
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Char | Returns: a Unicode character, or 0 if  | 
The Unicode character at this iterator is returned.  (Equivalent to
 operator* on a C++ iterator.)  If the element at this iterator is a
 non-character element, such as an image embedded in the buffer, the
 Unicode “unknown” character 0xFFFC is returned. If invoked on
 the end iterator, zero is returned; zero is not a valid Unicode character.
 So you can write a loop which ends when textIterGetChar
 returns 0.
getCharsInLine
textIterGetCharsInLine Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Int32 | Returns: number of characters in the line | 
Returns the number of characters in the line containing iter,
 including the paragraph delimiters.
getChildAnchor
textIterGetChildAnchor Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m TextChildAnchor | Returns: the anchor at  | 
If the location at iter contains a child anchor, the
 anchor is returned (with no new reference count added). Otherwise,
 Nothing is returned.
getLanguage
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Language | Returns: language in effect at  | 
Returns the language in effect at iter.
If no tags affecting language apply to iter, the return
 value is identical to that of getDefaultLanguage.
getLine
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Int32 | Returns: a line number | 
Returns the line number containing the iterator. Lines in
 a TextBuffer are numbered beginning with 0 for the first
 line in the buffer.
getLineIndex
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Int32 | Returns: distance from start of line, in bytes | 
Returns the byte index of the iterator, counting
 from the start of a newline-terminated line.
 Remember that TextBuffer encodes text in
 UTF-8, and that characters can require a variable
 number of bytes to represent.
getLineOffset
textIterGetLineOffset Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Int32 | Returns: offset from start of line | 
Returns the character offset of the iterator, counting from the start of a newline-terminated line. The first character on the line has offset 0.
getMarks
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m [TextMark] | Returns: list of  | 
Returns a list of all TextMark at this location. Because marks
 are not iterable (they don’t take up any "space" in the buffer,
 they are just marks in between iterable locations), multiple marks
 can exist in the same place. The returned list is not in any
 meaningful order.
getOffset
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Int32 | Returns: a character offset | 
Returns the character offset of an iterator.
 Each character in a TextBuffer has an offset,
 starting with 0 for the first character in the buffer.
 Use textBufferGetIterAtOffset to convert an
 offset back into an iterator.
getPaintable
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Paintable | Returns: the paintable at  | 
If the element at iter is a paintable, the paintable is returned
 (with no new reference count added). Otherwise, Nothing is returned.
getSlice
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextIter | 
 | 
| -> m Text | Returns: slice of text from the buffer | 
Returns the text in the given range. A “slice” is an array of characters encoded in UTF-8 format, including the Unicode “unknown” character 0xFFFC for iterable non-character elements in the buffer, such as images. Because images are encoded in the slice, byte and character offsets in the returned array will correspond to byte offsets in the text buffer. Note that 0xFFFC can occur in normal text as well, so it is not a reliable indicator that a paintable or widget is in the buffer.
getTags
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m [TextTag] | Returns: list of  | 
Returns a list of tags that apply to iter, in ascending order of
 priority (highest-priority tags are last). The TextTag in the
 list don’t have a reference added, but you have to free the list
 itself.
getText
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextIter | 
 | 
| -> m Text | Returns: array of characters from the buffer | 
Returns text in the given range.  If the range
 contains non-text elements such as images, the character and byte
 offsets in the returned string will not correspond to character and
 byte offsets in the buffer. If you want offsets to correspond, see
 textIterGetSlice.
getToggledTags
textIterGetToggledTags Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Bool | 
 | 
| -> m [TextTag] | Returns: tags toggled at this point | 
Returns a list of TextTag that are toggled on or off at this
 point.  (If toggledOn is True, the list contains tags that are
 toggled on.) If a tag is toggled on at iter, then some non-empty
 range of characters following iter has that tag applied to it.  If
 a tag is toggled off, then some non-empty range following iter
 does not have the tag applied to it.
getVisibleLineIndex
textIterGetVisibleLineIndex Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Int32 | Returns: byte index of  | 
Returns the number of bytes from the start of the
 line to the given iter, not counting bytes that
 are invisible due to tags with the “invisible” flag
 toggled on.
getVisibleLineOffset
textIterGetVisibleLineOffset Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Int32 | Returns: offset in visible characters from the start of the line | 
Returns the offset in characters from the start of the
 line to the given iter, not counting characters that
 are invisible due to tags with the “invisible” flag
 toggled on.
getVisibleSlice
textIterGetVisibleSlice Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextIter | 
 | 
| -> m Text | Returns: slice of text from the buffer | 
Like textIterGetSlice, but invisible text is not included.
 Invisible text is usually invisible because a TextTag with the
 “invisible” attribute turned on has been applied to it.
getVisibleText
textIterGetVisibleText Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextIter | 
 | 
| -> m Text | Returns: string containing visible text in the range | 
Like textIterGetText, but invisible text is not included.
 Invisible text is usually invisible because a TextTag with the
 “invisible” attribute turned on has been applied to it.
hasTag
Arguments
| :: (HasCallStack, MonadIO m, IsTextTag a) | |
| => TextIter | 
 | 
| -> a | 
 | 
| -> m Bool | Returns: whether  | 
Returns True if iter points to a character that is part of a range tagged
 with tag. See also textIterStartsTag and textIterEndsTag.
inRange
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextIter | 
 | 
| -> TextIter | 
 | 
| -> m Bool | Returns:  | 
Checks whether iter falls in the range [start, end).
 start and end must be in ascending order.
insideSentence
textIterInsideSentence Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Determines whether iter is inside a sentence (as opposed to in
 between two sentences, e.g. after a period and before the first
 letter of the next sentence).  Sentence boundaries are determined
 by Pango and should be correct for nearly any language (if not, the
 correct fix would be to the Pango text boundary algorithms).
insideWord
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Determines whether the character pointed by iter is part of a
 natural-language word (as opposed to say inside some whitespace).  Word
 breaks are determined by Pango and should be correct for nearly any language
 (if not, the correct fix would be to the Pango word break algorithms).
Note that if textIterStartsWord returns True, then this function
 returns True too, since iter points to the first character of the word.
isCursorPosition
textIterIsCursorPosition Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
See textIterForwardCursorPosition or LogAttr or
 break for details on what a cursor position is.
isEnd
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether  | 
Returns True if iter is the end iterator, i.e. one past the last
 dereferenceable iterator in the buffer. textIterIsEnd is
 the most efficient way to check whether an iterator is the end
 iterator.
isStart
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether  | 
Returns True if iter is the first iterator in the buffer, that is
 if iter has a character offset of 0.
order
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> TextIter | 
 | 
| -> m () | 
Swaps the value of first and second if second comes before
 first in the buffer. That is, ensures that first and second are
 in sequence. Most text buffer functions that take a range call this
 automatically on your behalf, so there’s no real reason to call it yourself
 in those cases. There are some exceptions, such as textIterInRange,
 that expect a pre-sorted range.
setLine
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m () | 
Moves iterator iter to the start of the line lineNumber.  If
 lineNumber is negative or larger than the number of lines in the
 buffer, moves iter to the start of the last line in the buffer.
setLineIndex
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m () | 
Same as textIterSetLineOffset, but works with a
 byte index. The given byte index must be at
 the start of a character, it can’t be in the middle of a UTF-8
 encoded character.
setLineOffset
textIterSetLineOffset Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m () | 
Moves iter within a line, to a new character
 (not byte) offset. The given character offset must be less than or
 equal to the number of characters in the line; if equal, iter
 moves to the start of the next line. See
 textIterSetLineIndex if you have a byte index rather than
 a character offset.
setOffset
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m () | 
Sets iter to point to charOffset. charOffset counts from the start
 of the entire text buffer, starting with 0.
setVisibleLineIndex
textIterSetVisibleLineIndex Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m () | 
Like textIterSetLineIndex, but the index is in visible
 bytes, i.e. text with a tag making it invisible is not counted
 in the index.
setVisibleLineOffset
textIterSetVisibleLineOffset Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> Int32 | 
 | 
| -> m () | 
Like textIterSetLineOffset, but the offset is in visible
 characters, i.e. text with a tag making it invisible is not
 counted in the offset.
startsLine
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns: whether  | 
Returns True if iter begins a paragraph,
 i.e. if textIterGetLineOffset would return 0.
 However this function is potentially more efficient than
 textIterGetLineOffset because it doesn’t have to compute
 the offset, it just has to see whether it’s 0.
startsSentence
textIterStartsSentence Source #
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Determines whether iter begins a sentence.  Sentence boundaries are
 determined by Pango and should be correct for nearly any language
 (if not, the correct fix would be to the Pango text boundary
 algorithms).
startsTag
Arguments
| :: (HasCallStack, MonadIO m, IsTextTag a) | |
| => TextIter | 
 | 
| -> Maybe a | |
| -> m Bool | Returns: whether  | 
Returns True if tag is toggled on at exactly this point. If tag
 is Nothing, returns True if any tag is toggled on at this point.
Note that if textIterStartsTag returns True, it means that iter is
 at the beginning of the tagged range, and that the
 character at iter is inside the tagged range. In other
 words, unlike textIterEndsTag, if textIterStartsTag returns
 True, textIterHasTag will also return True for the same
 parameters.
startsWord
Arguments
| :: (HasCallStack, MonadIO m) | |
| => TextIter | 
 | 
| -> m Bool | Returns:  | 
Determines whether iter begins a natural-language word.  Word
 breaks are determined by Pango and should be correct for nearly any
 language (if not, the correct fix would be to the Pango word break
 algorithms).
togglesTag
Arguments
| :: (HasCallStack, MonadIO m, IsTextTag a) | |
| => TextIter | 
 | 
| -> Maybe a | |
| -> m Bool | Returns: whether  | 
This is equivalent to (textIterStartsTag ||
 textIterEndsTag), i.e. it tells you whether a range with
 tag applied to it begins or ends at iter.