Simplify regular expression detection

Author: aleen42

src/data/store.ts

@@ -110,7 +110,7 @@ const isAcceptedProcessDeclarationPlugins = (plugins: DeclarationPlugin[]): bool
             && typeof plugin.priority == NUMBER_TYPE
             && Array.isArray(plugin.processors)
             && plugin.processors.every((processor: DeclarationPluginProcessor) =>
-                ({}).toString.call(processor.expr) === '[object RegExp]'
+                processor.expr instanceof RegExp
                 && typeof processor.action === FUNCTION_TYPE
             )
     );
@@ -272,4 +272,4 @@ const initKeyframesData = (): void => {
     store.keyframesRegExp = getKeyFramesRegExp(store.keyframesStringMap);
 };
 
-export { store, initStore, initKeyframesData };
+export { store, initStore, initKeyframesData };