servo/components/layout/css/matching.rs

774 lines
32 KiB
Rust

/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
//! High-level interface to CSS selector matching.
#![allow(unsafe_code)]
use animation;
use context::SharedLayoutContext;
use data::LayoutDataWrapper;
use incremental::{self, RestyleDamage};
use script::dom::bindings::inheritance::{CharacterDataTypeId, NodeTypeId};
use script::layout_interface::Animation;
use selectors::bloom::BloomFilter;
use selectors::matching::{CommonStyleAffectingAttributeMode, CommonStyleAffectingAttributes};
use selectors::matching::{common_style_affecting_attributes, rare_style_affecting_attributes};
use selectors::parser::PseudoElement;
use selectors::{Element};
use smallvec::SmallVec;
use std::borrow::ToOwned;
use std::hash::{Hash, Hasher};
use std::slice::Iter;
use std::sync::mpsc::Sender;
use std::sync::{Arc, Mutex};
use string_cache::{Atom, Namespace};
use style::node::TElementAttributes;
use style::properties::{ComputedValues, PropertyDeclaration, cascade};
use style::selector_matching::{DeclarationBlock, Stylist};
use style_traits::ParseErrorReporter;
use util::arc_ptr_eq;
use util::cache::{LRUCache, SimpleHashCache};
use util::opts;
use util::vec::ForgetfulSink;
use wrapper::{LayoutElement, LayoutNode};
pub struct ApplicableDeclarations {
pub normal: SmallVec<[DeclarationBlock; 16]>,
pub before: Vec<DeclarationBlock>,
pub after: Vec<DeclarationBlock>,
/// Whether the `normal` declarations are shareable with other nodes.
pub normal_shareable: bool,
}
impl ApplicableDeclarations {
pub fn new() -> ApplicableDeclarations {
ApplicableDeclarations {
normal: SmallVec::new(),
before: Vec::new(),
after: Vec::new(),
normal_shareable: false,
}
}
}
#[derive(Clone)]
pub struct ApplicableDeclarationsCacheEntry {
pub declarations: Vec<DeclarationBlock>,
}
impl ApplicableDeclarationsCacheEntry {
fn new(declarations: Vec<DeclarationBlock>) -> ApplicableDeclarationsCacheEntry {
ApplicableDeclarationsCacheEntry {
declarations: declarations,
}
}
}
impl PartialEq for ApplicableDeclarationsCacheEntry {
fn eq(&self, other: &ApplicableDeclarationsCacheEntry) -> bool {
let this_as_query = ApplicableDeclarationsCacheQuery::new(&*self.declarations);
this_as_query.eq(other)
}
}
impl Eq for ApplicableDeclarationsCacheEntry {}
impl Hash for ApplicableDeclarationsCacheEntry {
fn hash<H: Hasher>(&self, state: &mut H) {
let tmp = ApplicableDeclarationsCacheQuery::new(&*self.declarations);
tmp.hash(state);
}
}
struct ApplicableDeclarationsCacheQuery<'a> {
declarations: &'a [DeclarationBlock],
}
impl<'a> ApplicableDeclarationsCacheQuery<'a> {
fn new(declarations: &'a [DeclarationBlock]) -> ApplicableDeclarationsCacheQuery<'a> {
ApplicableDeclarationsCacheQuery {
declarations: declarations,
}
}
}
impl<'a> PartialEq for ApplicableDeclarationsCacheQuery<'a> {
fn eq(&self, other: &ApplicableDeclarationsCacheQuery<'a>) -> bool {
if self.declarations.len() != other.declarations.len() {
return false
}
for (this, other) in self.declarations.iter().zip(other.declarations) {
if !arc_ptr_eq(&this.declarations, &other.declarations) {
return false
}
}
true
}
}
impl<'a> Eq for ApplicableDeclarationsCacheQuery<'a> {}
impl<'a> PartialEq<ApplicableDeclarationsCacheEntry> for ApplicableDeclarationsCacheQuery<'a> {
fn eq(&self, other: &ApplicableDeclarationsCacheEntry) -> bool {
let other_as_query = ApplicableDeclarationsCacheQuery::new(&other.declarations);
self.eq(&other_as_query)
}
}
impl<'a> Hash for ApplicableDeclarationsCacheQuery<'a> {
fn hash<H: Hasher>(&self, state: &mut H) {
for declaration in self.declarations {
// Each declaration contians an Arc, which is a stable
// pointer; we use that for hashing and equality.
let ptr = &*declaration.declarations as *const Vec<PropertyDeclaration>;
ptr.hash(state);
}
}
}
static APPLICABLE_DECLARATIONS_CACHE_SIZE: usize = 32;
pub struct ApplicableDeclarationsCache {
cache: SimpleHashCache<ApplicableDeclarationsCacheEntry, Arc<ComputedValues>>,
}
impl ApplicableDeclarationsCache {
pub fn new() -> ApplicableDeclarationsCache {
ApplicableDeclarationsCache {
cache: SimpleHashCache::new(APPLICABLE_DECLARATIONS_CACHE_SIZE),
}
}
fn find(&self, declarations: &[DeclarationBlock]) -> Option<Arc<ComputedValues>> {
match self.cache.find(&ApplicableDeclarationsCacheQuery::new(declarations)) {
None => None,
Some(ref values) => Some((*values).clone()),
}
}
fn insert(&mut self, declarations: Vec<DeclarationBlock>, style: Arc<ComputedValues>) {
self.cache.insert(ApplicableDeclarationsCacheEntry::new(declarations), style)
}
pub fn evict_all(&mut self) {
self.cache.evict_all();
}
}
/// An LRU cache of the last few nodes seen, so that we can aggressively try to reuse their styles.
pub struct StyleSharingCandidateCache {
cache: LRUCache<StyleSharingCandidate, ()>,
}
fn create_common_style_affecting_attributes_from_element<'le, E: LayoutElement<'le>>(element: &E)
-> CommonStyleAffectingAttributes {
let mut flags = CommonStyleAffectingAttributes::empty();
for attribute_info in &common_style_affecting_attributes() {
match attribute_info.mode {
CommonStyleAffectingAttributeMode::IsPresent(flag) => {
if element.get_attr(&ns!(), &attribute_info.atom).is_some() {
flags.insert(flag)
}
}
CommonStyleAffectingAttributeMode::IsEqual(target_value, flag) => {
match element.get_attr(&ns!(), &attribute_info.atom) {
Some(element_value) if element_value == target_value => {
flags.insert(flag)
}
_ => {}
}
}
}
}
flags
}
#[derive(Clone)]
pub struct StyleSharingCandidate {
pub style: Arc<ComputedValues>,
pub parent_style: Arc<ComputedValues>,
pub local_name: Atom,
// FIXME(pcwalton): Should be a list of atoms instead.
pub class: Option<String>,
pub namespace: Namespace,
pub common_style_affecting_attributes: CommonStyleAffectingAttributes,
pub link: bool,
}
impl PartialEq for StyleSharingCandidate {
fn eq(&self, other: &StyleSharingCandidate) -> bool {
arc_ptr_eq(&self.style, &other.style) &&
arc_ptr_eq(&self.parent_style, &other.parent_style) &&
self.local_name == other.local_name &&
self.class == other.class &&
self.link == other.link &&
self.namespace == other.namespace &&
self.common_style_affecting_attributes == other.common_style_affecting_attributes
}
}
impl StyleSharingCandidate {
/// Attempts to create a style sharing candidate from this node. Returns
/// the style sharing candidate or `None` if this node is ineligible for
/// style sharing.
fn new<'le, E: LayoutElement<'le>>(element: &E) -> Option<StyleSharingCandidate> {
let parent_element = match element.parent_element() {
None => return None,
Some(parent_element) => parent_element,
};
let style = unsafe {
match *element.as_node().borrow_layout_data_unchecked() {
None => return None,
Some(ref layout_data_ref) => {
match layout_data_ref.shared_data.style {
None => return None,
Some(ref data) => (*data).clone(),
}
}
}
};
let parent_style = unsafe {
match *parent_element.as_node().borrow_layout_data_unchecked() {
None => return None,
Some(ref parent_layout_data_ref) => {
match parent_layout_data_ref.shared_data.style {
None => return None,
Some(ref data) => (*data).clone(),
}
}
}
};
if element.style_attribute().is_some() {
return None
}
Some(StyleSharingCandidate {
style: style,
parent_style: parent_style,
local_name: element.get_local_name().clone(),
class: element.get_attr(&ns!(), &atom!("class"))
.map(|string| string.to_owned()),
link: element.is_link(),
namespace: (*element.get_namespace()).clone(),
common_style_affecting_attributes:
create_common_style_affecting_attributes_from_element::<'le, E>(&element)
})
}
fn can_share_style_with<'a, E: LayoutElement<'a>>(&self, element: &E) -> bool {
if *element.get_local_name() != self.local_name {
return false
}
// FIXME(pcwalton): Use `each_class` here instead of slow string comparison.
match (&self.class, element.get_attr(&ns!(), &atom!("class"))) {
(&None, Some(_)) | (&Some(_), None) => return false,
(&Some(ref this_class), Some(element_class)) if
element_class != &**this_class => {
return false
}
(&Some(_), Some(_)) | (&None, None) => {}
}
if *element.get_namespace() != self.namespace {
return false
}
let mut matching_rules = ForgetfulSink::new();
element.synthesize_presentational_hints_for_legacy_attributes(&mut matching_rules);
if !matching_rules.is_empty() {
return false;
}
// FIXME(pcwalton): It's probably faster to iterate over all the element's attributes and
// use the {common, rare}-style-affecting-attributes tables as lookup tables.
for attribute_info in &common_style_affecting_attributes() {
match attribute_info.mode {
CommonStyleAffectingAttributeMode::IsPresent(flag) => {
if self.common_style_affecting_attributes.contains(flag) !=
element.get_attr(&ns!(), &attribute_info.atom).is_some() {
return false
}
}
CommonStyleAffectingAttributeMode::IsEqual(target_value, flag) => {
match element.get_attr(&ns!(), &attribute_info.atom) {
Some(ref element_value) if self.common_style_affecting_attributes
.contains(flag) &&
*element_value != target_value => {
return false
}
Some(_) if !self.common_style_affecting_attributes.contains(flag) => {
return false
}
None if self.common_style_affecting_attributes.contains(flag) => {
return false
}
_ => {}
}
}
}
}
for attribute_name in &rare_style_affecting_attributes() {
if element.get_attr(&ns!(), attribute_name).is_some() {
return false
}
}
if element.is_link() != self.link {
return false
}
// TODO(pcwalton): We don't support visited links yet, but when we do there will need to
// be some logic here.
true
}
}
static STYLE_SHARING_CANDIDATE_CACHE_SIZE: usize = 40;
impl StyleSharingCandidateCache {
pub fn new() -> StyleSharingCandidateCache {
StyleSharingCandidateCache {
cache: LRUCache::new(STYLE_SHARING_CANDIDATE_CACHE_SIZE),
}
}
pub fn iter(&self) -> Iter<(StyleSharingCandidate, ())> {
self.cache.iter()
}
pub fn insert_if_possible<'le, E: LayoutElement<'le>>(&mut self, element: &E) {
match StyleSharingCandidate::new(element) {
None => {}
Some(candidate) => self.cache.insert(candidate, ())
}
}
pub fn touch(&mut self, index: usize) {
self.cache.touch(index)
}
}
/// The results of attempting to share a style.
pub enum StyleSharingResult {
/// We didn't find anybody to share the style with.
CannotShare,
/// The node's style can be shared. The integer specifies the index in the LRU cache that was
/// hit and the damage that was done.
StyleWasShared(usize, RestyleDamage),
}
pub trait ElementMatchMethods<'le, ConcreteLayoutElement: LayoutElement<'le>> {
fn match_element(&self,
stylist: &Stylist,
parent_bf: Option<&BloomFilter>,
applicable_declarations: &mut ApplicableDeclarations)
-> bool;
/// Attempts to share a style with another node. This method is unsafe because it depends on
/// the `style_sharing_candidate_cache` having only live nodes in it, and we have no way to
/// guarantee that at the type system level yet.
unsafe fn share_style_if_possible(&self,
style_sharing_candidate_cache:
&mut StyleSharingCandidateCache,
parent: Option<ConcreteLayoutElement::ConcreteLayoutNode>)
-> StyleSharingResult;
}
pub trait MatchMethods<'ln, ConcreteLayoutNode: LayoutNode<'ln>> {
/// Inserts and removes the matching `Descendant` selectors from a bloom
/// filter. This is used to speed up CSS selector matching to remove
/// unnecessary tree climbs for `Descendant` queries.
///
/// A bloom filter of the local names, namespaces, IDs, and classes is kept.
/// Therefore, each node must have its matching selectors inserted _after_
/// its own selector matching and _before_ its children start.
fn insert_into_bloom_filter(&self, bf: &mut BloomFilter);
/// After all the children are done css selector matching, this must be
/// called to reset the bloom filter after an `insert`.
fn remove_from_bloom_filter(&self, bf: &mut BloomFilter);
unsafe fn cascade_node(&self,
layout_context: &SharedLayoutContext,
parent: Option<ConcreteLayoutNode>,
applicable_declarations: &ApplicableDeclarations,
applicable_declarations_cache: &mut ApplicableDeclarationsCache,
new_animations_sender: &Mutex<Sender<Animation>>);
}
trait PrivateMatchMethods {
fn cascade_node_pseudo_element(&self,
layout_context: &SharedLayoutContext,
parent_style: Option<&Arc<ComputedValues>>,
applicable_declarations: &[DeclarationBlock],
style: &mut Option<Arc<ComputedValues>>,
applicable_declarations_cache:
&mut ApplicableDeclarationsCache,
new_animations_sender: &Mutex<Sender<Animation>>,
shareable: bool,
animate_properties: bool)
-> RestyleDamage;
fn update_animations_for_cascade(&self,
layout_context: &SharedLayoutContext,
style: &mut Option<Arc<ComputedValues>>)
-> bool;
}
trait PrivateElementMatchMethods<'le, ConcreteLayoutElement: LayoutElement<'le>> {
fn share_style_with_candidate_if_possible(&self,
parent_node: Option<ConcreteLayoutElement::ConcreteLayoutNode>,
candidate: &StyleSharingCandidate)
-> Option<Arc<ComputedValues>>;
}
impl<'ln, ConcreteLayoutNode> PrivateMatchMethods for ConcreteLayoutNode
where ConcreteLayoutNode: LayoutNode<'ln> {
fn cascade_node_pseudo_element(&self,
layout_context: &SharedLayoutContext,
parent_style: Option<&Arc<ComputedValues>>,
applicable_declarations: &[DeclarationBlock],
style: &mut Option<Arc<ComputedValues>>,
applicable_declarations_cache:
&mut ApplicableDeclarationsCache,
new_animations_sender: &Mutex<Sender<Animation>>,
shareable: bool,
animate_properties: bool)
-> RestyleDamage {
let mut cacheable = true;
if animate_properties {
cacheable = !self.update_animations_for_cascade(layout_context, style) && cacheable;
}
let mut this_style;
match parent_style {
Some(ref parent_style) => {
let cache_entry = applicable_declarations_cache.find(applicable_declarations);
let cached_computed_values = match cache_entry {
None => None,
Some(ref style) => Some(&**style),
};
let (the_style, is_cacheable) = cascade(layout_context.viewport_size,
applicable_declarations,
shareable,
Some(&***parent_style),
cached_computed_values,
layout_context.error_reporter.clone());
cacheable = cacheable && is_cacheable;
this_style = the_style
}
None => {
let (the_style, is_cacheable) = cascade(layout_context.viewport_size,
applicable_declarations,
shareable,
None,
None,
layout_context.error_reporter.clone());
cacheable = cacheable && is_cacheable;
this_style = the_style
}
};
// Trigger transitions if necessary. This will reset `this_style` back to its old value if
// it did trigger a transition.
if animate_properties {
if let Some(ref style) = *style {
let animations_started =
animation::start_transitions_if_applicable(new_animations_sender,
self.opaque(),
&**style,
&mut this_style);
cacheable = cacheable && !animations_started
}
}
// Calculate style difference.
let this_style = Arc::new(this_style);
let damage = incremental::compute_damage(style, &*this_style);
// Cache the resolved style if it was cacheable.
if cacheable {
applicable_declarations_cache.insert(applicable_declarations.to_vec(),
this_style.clone());
}
// Write in the final style and return the damage done to our caller.
*style = Some(this_style);
damage
}
fn update_animations_for_cascade(&self,
layout_context: &SharedLayoutContext,
style: &mut Option<Arc<ComputedValues>>)
-> bool {
let style = match *style {
None => return false,
Some(ref mut style) => style,
};
// Finish any expired transitions.
let this_opaque = self.opaque();
let had_animations_to_expire;
{
let all_expired_animations = layout_context.expired_animations.read().unwrap();
let animations_to_expire = all_expired_animations.get(&this_opaque);
had_animations_to_expire = animations_to_expire.is_some();
if let Some(ref animations) = animations_to_expire {
for animation in *animations {
animation.property_animation.update(&mut *Arc::make_mut(style), 1.0);
}
}
}
if had_animations_to_expire {
layout_context.expired_animations.write().unwrap().remove(&this_opaque);
}
// Merge any running transitions into the current style, and cancel them.
let had_running_animations = layout_context.running_animations
.read()
.unwrap()
.get(&this_opaque)
.is_some();
if had_running_animations {
let mut all_running_animations = layout_context.running_animations.write().unwrap();
for running_animation in all_running_animations.get(&this_opaque).unwrap() {
animation::update_style_for_animation(running_animation, style, None);
}
all_running_animations.remove(&this_opaque);
}
had_animations_to_expire || had_running_animations
}
}
impl<'le, ConcreteLayoutElement> PrivateElementMatchMethods<'le, ConcreteLayoutElement>
for ConcreteLayoutElement
where ConcreteLayoutElement: LayoutElement<'le> {
fn share_style_with_candidate_if_possible(&self,
parent_node: Option<ConcreteLayoutElement::ConcreteLayoutNode>,
candidate: &StyleSharingCandidate)
-> Option<Arc<ComputedValues>> {
let parent_node = match parent_node {
Some(ref parent_node) if parent_node.as_element().is_some() => parent_node,
Some(_) | None => return None,
};
let parent_layout_data: &Option<LayoutDataWrapper> = unsafe {
&*parent_node.borrow_layout_data_unchecked()
};
match *parent_layout_data {
Some(ref parent_layout_data_ref) => {
// Check parent style.
let parent_style = parent_layout_data_ref.shared_data.style.as_ref().unwrap();
if !arc_ptr_eq(parent_style, &candidate.parent_style) {
return None
}
// Check tag names, classes, etc.
if !candidate.can_share_style_with(self) {
return None
}
return Some(candidate.style.clone())
}
_ => {}
}
None
}
}
impl<'le, ConcreteLayoutElement> ElementMatchMethods<'le, ConcreteLayoutElement>
for ConcreteLayoutElement
where ConcreteLayoutElement: LayoutElement<'le> {
fn match_element(&self,
stylist: &Stylist,
parent_bf: Option<&BloomFilter>,
applicable_declarations: &mut ApplicableDeclarations)
-> bool {
let style_attribute = self.style_attribute().as_ref();
applicable_declarations.normal_shareable =
stylist.push_applicable_declarations(self,
parent_bf,
style_attribute,
None,
&mut applicable_declarations.normal);
stylist.push_applicable_declarations(self,
parent_bf,
None,
Some(PseudoElement::Before),
&mut applicable_declarations.before);
stylist.push_applicable_declarations(self,
parent_bf,
None,
Some(PseudoElement::After),
&mut applicable_declarations.after);
applicable_declarations.normal_shareable &&
applicable_declarations.before.is_empty() &&
applicable_declarations.after.is_empty()
}
unsafe fn share_style_if_possible(&self,
style_sharing_candidate_cache:
&mut StyleSharingCandidateCache,
parent: Option<ConcreteLayoutElement::ConcreteLayoutNode>)
-> StyleSharingResult {
if opts::get().disable_share_style_cache {
return StyleSharingResult::CannotShare
}
if self.style_attribute().is_some() {
return StyleSharingResult::CannotShare
}
if self.get_attr(&ns!(), &atom!("id")).is_some() {
return StyleSharingResult::CannotShare
}
for (i, &(ref candidate, ())) in style_sharing_candidate_cache.iter().enumerate() {
match self.share_style_with_candidate_if_possible(parent.clone(), candidate) {
Some(shared_style) => {
// Yay, cache hit. Share the style.
let node = self.as_node();
let mut layout_data_ref = node.mutate_layout_data();
let shared_data = &mut layout_data_ref.as_mut().unwrap().shared_data;
let style = &mut shared_data.style;
let damage = incremental::compute_damage(style, &*shared_style);
*style = Some(shared_style);
return StyleSharingResult::StyleWasShared(i, damage)
}
None => {}
}
}
StyleSharingResult::CannotShare
}
}
impl<'ln, ConcreteLayoutNode> MatchMethods<'ln, ConcreteLayoutNode>
for ConcreteLayoutNode
where ConcreteLayoutNode: LayoutNode<'ln> {
// The below two functions are copy+paste because I can't figure out how to
// write a function which takes a generic function. I don't think it can
// be done.
//
// Ideally, I'd want something like:
//
// > fn with_really_simple_selectors(&self, f: <H: Hash>|&H|);
// In terms of `SimpleSelector`s, these two functions will insert and remove:
// - `SimpleSelector::LocalName`
// - `SimpleSelector::Namepace`
// - `SimpleSelector::ID`
// - `SimpleSelector::Class`
fn insert_into_bloom_filter(&self, bf: &mut BloomFilter) {
// Only elements are interesting.
if let Some(element) = self.as_element() {
bf.insert(element.get_local_name());
bf.insert(element.get_namespace());
element.get_id().map(|id| bf.insert(&id));
// TODO: case-sensitivity depends on the document type and quirks mode
element.each_class(|class| bf.insert(class));
}
}
fn remove_from_bloom_filter(&self, bf: &mut BloomFilter) {
// Only elements are interesting.
if let Some(element) = self.as_element() {
bf.remove(element.get_local_name());
bf.remove(element.get_namespace());
element.get_id().map(|id| bf.remove(&id));
// TODO: case-sensitivity depends on the document type and quirks mode
element.each_class(|class| bf.remove(class));
}
}
unsafe fn cascade_node(&self,
layout_context: &SharedLayoutContext,
parent: Option<ConcreteLayoutNode>,
applicable_declarations: &ApplicableDeclarations,
applicable_declarations_cache: &mut ApplicableDeclarationsCache,
new_animations_sender: &Mutex<Sender<Animation>>) {
// Get our parent's style. This must be unsafe so that we don't touch the parent's
// borrow flags.
//
// FIXME(pcwalton): Isolate this unsafety into the `wrapper` module to allow
// enforced safe, race-free access to the parent style.
let parent_style = match parent {
None => None,
Some(parent_node) => {
let parent_layout_data_ref = parent_node.borrow_layout_data_unchecked();
let parent_layout_data = (&*parent_layout_data_ref).as_ref()
.expect("no parent data!?");
let parent_style = parent_layout_data.shared_data
.style
.as_ref()
.expect("parent hasn't been styled yet!");
Some(parent_style)
}
};
let mut layout_data_ref = self.mutate_layout_data();
match *layout_data_ref {
None => panic!("no layout data"),
Some(ref mut layout_data) => {
match self.type_id() {
NodeTypeId::CharacterData(CharacterDataTypeId::Text) => {
// Text nodes get a copy of the parent style. This ensures
// that during fragment construction any non-inherited
// CSS properties (such as vertical-align) are correctly
// set on the fragment(s).
let cloned_parent_style = parent_style.unwrap().clone();
layout_data.shared_data.style = Some(cloned_parent_style);
}
_ => {
let mut damage = self.cascade_node_pseudo_element(
layout_context,
parent_style,
&applicable_declarations.normal,
&mut layout_data.shared_data.style,
applicable_declarations_cache,
new_animations_sender,
applicable_declarations.normal_shareable,
true);
if applicable_declarations.before.len() > 0 {
damage = damage | self.cascade_node_pseudo_element(
layout_context,
Some(layout_data.shared_data.style.as_ref().unwrap()),
&*applicable_declarations.before,
&mut layout_data.data.before_style,
applicable_declarations_cache,
new_animations_sender,
false,
false);
}
if applicable_declarations.after.len() > 0 {
damage = damage | self.cascade_node_pseudo_element(
layout_context,
Some(layout_data.shared_data.style.as_ref().unwrap()),
&*applicable_declarations.after,
&mut layout_data.data.after_style,
applicable_declarations_cache,
new_animations_sender,
false,
false);
}
layout_data.data.restyle_damage = damage;
}
}
}
}
}
}