public function beforeSending(Closure $callback): self
    {
        return tap($this, function () use ($callback) {
            $this->beforeSendingCallbacks[] = $callback;
        });
    }
public function beforeSending(Closure $callback): self
    {
        return tap($this, function () use ($callback) {
            $this->beforeSendingCallbacks[] = $callback;
        });
    }
public function beforeSending ( Closure $ callback ) : self { return tap ( $ this , function ( ) use ( $ callback ) { $ this -> beforeSendingCallbacks [ ] = $ callback ; } ) ; }
Set the pre-request Callback.

@param \Closure $callback

@return \BrianFaust\Http\PendingHttpRequest
Set the pre - request Callback .