59 lines
816 B
JavaScript
59 lines
816 B
JavaScript
export default class ChainMap {
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constructor() {
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this.weakMap = new WeakMap();
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}
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get( keys ) {
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let map = this.weakMap;
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for ( let i = 0; i < keys.length; i ++ ) {
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map = map.get( keys[ i ] );
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if ( map === undefined ) return undefined;
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}
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return map.get( keys[ keys.length - 1 ] );
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}
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set( keys, value ) {
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let map = this.weakMap;
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for ( let i = 0; i < keys.length; i ++ ) {
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const key = keys[ i ];
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if ( map.has( key ) === false ) map.set( key, new WeakMap() );
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map = map.get( key );
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}
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return map.set( keys[ keys.length - 1 ], value );
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}
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delete( keys ) {
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let map = this.weakMap;
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for ( let i = 0; i < keys.length; i ++ ) {
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map = map.get( keys[ i ] );
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if ( map === undefined ) return false;
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}
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return map.delete( keys[ keys.length - 1 ] );
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}
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}
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