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node_modules/watcher/src/lazy_map_set.ts

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+
+/* IMPORT */
+
+import Utils from './utils';
+
+/* MAIN */
+
+//TODO: Maybe publish this as a standalone module
+
+class LazyMapSet<K, V> {
+
+  /* VARIABLES */
+
+  private map: Map<K, Set<V> | V> = new Map ();
+
+  /* API */
+
+  clear (): void {
+
+    this.map.clear ();
+
+  }
+
+  delete ( key: K, value?: V ): boolean {
+
+    if ( Utils.lang.isUndefined ( value ) ) {
+
+      return this.map.delete ( key );
+
+    } else if ( this.map.has ( key ) ) {
+
+      const values = this.map.get ( key );
+
+      if ( Utils.lang.isSet ( values ) ) {
+
+        const deleted = values.delete ( value );
+
+        if ( !values.size ) {
+
+          this.map.delete ( key );
+
+        }
+
+        return deleted;
+
+      } else if ( values === value ) {
+
+        this.map.delete ( key );
+
+        return true;
+
+      }
+
+    }
+
+    return false;
+
+  }
+
+  find ( key: K, iterator: ( value: V ) => boolean ): V | undefined {
+
+    if ( this.map.has ( key ) ) {
+
+      const values = this.map.get ( key );
+
+      if ( Utils.lang.isSet ( values ) ) {
+
+        return Array.from ( values ).find ( iterator );
+
+      } else if ( iterator ( values! ) ) { //TSC
+
+        return values;
+
+      }
+
+    }
+
+    return undefined;
+
+  }
+
+  get ( key: K ): Set<V> | V | undefined {
+
+    return this.map.get ( key );
+
+  }
+
+  has ( key: K, value?: V ): boolean {
+
+    if ( Utils.lang.isUndefined ( value ) ) {
+
+      return this.map.has ( key );
+
+    } else if ( this.map.has ( key ) ) {
+
+      const values = this.map.get ( key );
+
+      if ( Utils.lang.isSet ( values ) ) {
+
+        return values.has ( value );
+
+      } else {
+
+        return ( values === value );
+
+      }
+
+    }
+
+    return false;
+
+  }
+
+  set ( key: K, value: V ): this {
+
+    if ( this.map.has ( key ) ) {
+
+      const values = this.map.get ( key );
+
+      if ( Utils.lang.isSet ( values ) ) {
+
+        values.add ( value );
+
+      } else if ( values !== value ) {
+
+        this.map.set ( key, new Set ([ values!, value ]) ); //TSC
+
+      }
+
+    } else {
+
+      this.map.set ( key, value );
+
+    }
+
+    return this;
+
+  }
+
+}
+
+/* EXPORT */
+
+export default LazyMapSet;