Prevent adding multiple event listeners

src/maska.js

@@ -31,15 +31,19 @@ export default class Maska {
         el.dataset.mask = this._opts.mask
       }
       this.updateValue(el)
+      if (!el.dataset.maskInited) {
+        el.dataset.maskInited = true
         el.addEventListener('input', evt => this.updateValue(evt.target))
       }
     }
+  }
 
   destroy () {
     for (let i = 0; i < this._el.length; i++) {
       const el = findInputElement(this._el[i])
       el.removeEventListener('input', evt => this.updateValue(evt.target))
       delete el.dataset.mask
+      delete el.dataset.maskInited
     }
   }