concrete/src/Statistics/UsageTracker/AggregateTracker.php
public function addTracker($tracker, callable $creator)
    {
        $this->creators[$tracker] = $creator;
        $this->map[] = $tracker;

        if (isset($this->trackers[$tracker])) {
            unset($this->trackers[$tracker]);
        }

        return $this;
    }
public function addTracker($tracker, callable $creator)
    {
        $this->creators[$tracker] = $creator;
        $this->map[] = $tracker;

        if (isset($this->trackers[$tracker])) {
            unset($this->trackers[$tracker]);
        }

        return $this;
    }
public function addTracker ( $ tracker , callable $ creator ) { $ this -> creators [ $ tracker ] = $ creator ; $ this -> map [ ] = $ tracker ; if ( isset ( $ this -> trackers [ $ tracker ] ) ) { unset ( $ this -> trackers [ $ tracker ] ) ; } return $ this ; }
Register a custom tracker creator Closure.

@param  string $tracker The handle of the tracker
@param  callable $creator The closure responsible for returning the new tracker instance
@return static
Register a custom tracker creator Closure .