style(Store): rename select input variable

modules/store/src/store.ts

@@ -178,24 +178,22 @@ export function select<
  * fixed length tuples type in typescript 2.7
  */
 export function select<State, Props = any, Result = any>(
-  props: Props,
+  propsOrPath: Props,
   ...paths: string[]
 ): (source$: Observable<State>) => Observable<Result>;
 export function select<State, Props, K>(
   pathOrMapFn: (state: State, props?: Props) => any | string,
-  props: Props,
+  props: Props | string,
   ...paths: string[]
 ) {
   return function selectOperator(source$: Observable<State>): Observable<K> {
     let mapped$: Observable<any>;
 
     if (typeof pathOrMapFn === 'string') {
-      mapped$ =
-        typeof props === 'string'
-          ? source$.pipe(pluck(pathOrMapFn, props, ...paths))
-          : source$.pipe(pluck(pathOrMapFn, ...paths));
+      const pathSlices = [<string>props, ...paths].filter(Boolean);
+      mapped$ = source$.pipe(pluck(pathOrMapFn, ...pathSlices));
     } else if (typeof pathOrMapFn === 'function') {
-      mapped$ = source$.pipe(map(source => pathOrMapFn(source, props)));
+      mapped$ = source$.pipe(map(source => pathOrMapFn(source, <Props>props)));
     } else {
       throw new TypeError(
         `Unexpected type '${typeof pathOrMapFn}' in select operator,` +