sync() {
    for (const [name, val] of this.vars_) {
      val.sync();
    }
  }
/** Update all variables with DOM elements. */
Update all variables with DOM elements.
Update all variables with DOM elements .
sync() {
    for (const [name, val] of this.vars_) {
      val.sync();
    }
  }
sync ( ) { for ( const [ name , val ] of this . vars_ ) { val . sync ( ) ; } }
Update all variables with DOM elements.
Update all variables with DOM elements .