gi-pango-1.0.18: Pango bindings

CopyrightWill Thompson Iñaki García Etxebarria and Jonas Platte
LicenseLGPL-2.1
MaintainerIñaki García Etxebarria (inaki@blueleaf.cc)
Safe HaskellNone
LanguageHaskell2010

GI.Pango.Structs.AttrList

Contents

Description

The AttrList structure represents a list of attributes that apply to a section of text. The attributes are, in general, allowed to overlap in an arbitrary fashion, however, if the attributes are manipulated only through attrListChange, the overlap between properties will meet stricter criteria.

Since the AttrList structure is stored as a linear list, it is not suitable for storing attributes for large amounts of text. In general, you should not use a single AttrList for more than one paragraph of text.

Synopsis

Exported types

newtype AttrList Source #

Memory-managed wrapper type.

Constructors

AttrList (ManagedPtr AttrList) 
Instances
BoxedObject AttrList Source # 
Instance details

Defined in GI.Pango.Structs.AttrList

Methods

boxedType :: AttrList -> IO GType #

noAttrList :: Maybe AttrList Source #

A convenience alias for Nothing :: Maybe AttrList.

Methods

change

attrListChange Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> AttrList

list: a AttrList

-> Attribute

attr: the attribute to insert. Ownership of this value is assumed by the list.

-> m () 

Insert the given attribute into the AttrList. It will replace any attributes of the same type on that segment and be merged with any adjoining attributes that are identical.

This function is slower than attrListInsert for creating a attribute list in order (potentially much slower for large lists). However, attrListInsert is not suitable for continually changing a set of attributes since it never removes or combines existing attributes.

copy

attrListCopy Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> AttrList

list: a AttrList, may be Nothing

-> m (Maybe AttrList)

Returns: the newly allocated AttrList, with a reference count of one, which should be freed with attrListUnref. Returns Nothing if list was Nothing.

Copy list and return an identical new list.

filter

attrListFilter Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> AttrList

list: a AttrList

-> AttrFilterFunc

func: callback function; returns True if an attribute should be filtered out.

-> m (Maybe AttrList)

Returns: the new AttrList or Nothing if no attributes of the given types were found.

Given a AttrList and callback function, removes any elements of list for which func returns True and inserts them into a new list.

Since: 1.2

insert

attrListInsert Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> AttrList

list: a AttrList

-> Attribute

attr: the attribute to insert. Ownership of this value is assumed by the list.

-> m () 

Insert the given attribute into the AttrList. It will be inserted after all other attributes with a matching startIndex.

insertBefore

attrListInsertBefore Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> AttrList

list: a AttrList

-> Attribute

attr: the attribute to insert. Ownership of this value is assumed by the list.

-> m () 

Insert the given attribute into the AttrList. It will be inserted before all other attributes with a matching startIndex.

new

attrListNew Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> m AttrList

Returns: the newly allocated AttrList, which should be freed with attrListUnref.

Create a new empty attribute list with a reference count of one.

ref

attrListRef Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> AttrList

list: a AttrList, may be Nothing

-> m AttrList

Returns: The attribute list passed in

Increase the reference count of the given attribute list by one.

Since: 1.10

splice

attrListSplice Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> AttrList

list: a AttrList

-> AttrList

other: another AttrList

-> Int32

pos: the position in list at which to insert other

-> Int32

len: the length of the spliced segment. (Note that this must be specified since the attributes in other may only be present at some subsection of this range)

-> m () 

This function opens up a hole in list, fills it in with attributes from the left, and then merges other on top of the hole.

This operation is equivalent to stretching every attribute that applies at position pos in list by an amount len, and then calling attrListChange with a copy of each attribute in other in sequence (offset in position by pos).

This operation proves useful for, for instance, inserting a pre-edit string in the middle of an edit buffer.

unref

attrListUnref Source #

Arguments

:: (HasCallStack, MonadIO m) 
=> AttrList

list: a AttrList, may be Nothing

-> m () 

Decrease the reference count of the given attribute list by one. If the result is zero, free the attribute list and the attributes it contains.