bd65f58784
`LView`, `LContainer`, `StylingContext` are all arrays which wrap either an `HTMLElement`, `LView`, `LContainer`, `StylingContext`. It is often necessary to retrieve the correct type of element from the location which means that we often have to wrap the arrays. Logically it makes more sense if the thing which we are wrapping is at `0` location. Also it may be more performant since data is more local which may result in more L2 cache hits in CPU. PR Close #28947
97 lines
3.6 KiB
TypeScript
97 lines
3.6 KiB
TypeScript
/**
|
|
* @license
|
|
* Copyright Google Inc. All Rights Reserved.
|
|
*
|
|
* Use of this source code is governed by an MIT-style license that can be
|
|
* found in the LICENSE file at https://angular.io/license
|
|
*/
|
|
|
|
import {LQueries} from './query';
|
|
import {RComment, RElement} from './renderer';
|
|
import {StylingContext} from './styling';
|
|
import {HOST, LView, NEXT, PARENT, QUERIES} from './view';
|
|
|
|
|
|
/**
|
|
* Below are constants for LContainer indices to help us look up LContainer members
|
|
* without having to remember the specific indices.
|
|
* Uglify will inline these when minifying so there shouldn't be a cost.
|
|
*/
|
|
export const ACTIVE_INDEX = 1;
|
|
export const VIEWS = 2;
|
|
// PARENT, NEXT, QUERIES, and HOST are indices 2, 3, 4, and 5.
|
|
// As we already have these constants in LView, we don't need to re-create them.
|
|
export const NATIVE = 6;
|
|
// Because interfaces in TS/JS cannot be instanceof-checked this means that we
|
|
// need to rely on predictable characteristics of data-structures to check if they
|
|
// are what we expect for them to be. The `LContainer` interface code below has a
|
|
// fixed length and the constant value below references that. Using the length value
|
|
// below we can predictably gaurantee that we are dealing with an `LContainer` array.
|
|
// This value MUST be kept up to date with the length of the `LContainer` array
|
|
// interface below so that runtime type checking can work.
|
|
export const LCONTAINER_LENGTH = 7;
|
|
|
|
/**
|
|
* The state associated with a container.
|
|
*
|
|
* This is an array so that its structure is closer to LView. This helps
|
|
* when traversing the view tree (which is a mix of containers and component
|
|
* views), so we can jump to viewOrContainer[NEXT] in the same way regardless
|
|
* of type.
|
|
*/
|
|
export interface LContainer extends Array<any> {
|
|
/**
|
|
* The host element of this LContainer.
|
|
*
|
|
* The host could be an LView if this container is on a component node.
|
|
* In that case, the component LView is its HOST.
|
|
*
|
|
* It could also be a styling context if this is a node with a style/class
|
|
* binding.
|
|
*/
|
|
readonly[HOST]: RElement|RComment|StylingContext|LView;
|
|
|
|
/**
|
|
* The next active index in the views array to read or write to. This helps us
|
|
* keep track of where we are in the views array.
|
|
* In the case the LContainer is created for a ViewContainerRef,
|
|
* it is set to null to identify this scenario, as indices are "absolute" in that case,
|
|
* i.e. provided directly by the user of the ViewContainerRef API.
|
|
*/
|
|
[ACTIVE_INDEX]: number;
|
|
|
|
/**
|
|
* A list of the container's currently active child views. Views will be inserted
|
|
* here as they are added and spliced from here when they are removed. We need
|
|
* to keep a record of current views so we know which views are already in the DOM
|
|
* (and don't need to be re-added) and so we can remove views from the DOM when they
|
|
* are no longer required.
|
|
*/
|
|
[VIEWS]: LView[];
|
|
|
|
/**
|
|
* Access to the parent view is necessary so we can propagate back
|
|
* up from inside a container to parent[NEXT].
|
|
*/
|
|
[PARENT]: LView;
|
|
|
|
/**
|
|
* This allows us to jump from a container to a sibling container or component
|
|
* view with the same parent, so we can remove listeners efficiently.
|
|
*/
|
|
[NEXT]: LView|LContainer|null;
|
|
|
|
/**
|
|
* Queries active for this container - all the views inserted to / removed from
|
|
* this container are reported to queries referenced here.
|
|
*/
|
|
[QUERIES]: LQueries|null;
|
|
|
|
/** The comment element that serves as an anchor for this LContainer. */
|
|
readonly[NATIVE]: RComment;
|
|
}
|
|
|
|
// Note: This hack is necessary so we don't erroneously get a circular dependency
|
|
// failure based on types.
|
|
export const unusedValueExportToPlacateAjd = 1;
|