src/Pipeline/Simple.php
protected function handleStage(&$stages, $stage)
    {
        if ($stage instanceof Pipeline) {
            $stages = array_merge($stages, $stage->stages());
        } else {
            $stages[] = is_callable($stage) ? new Callback($stage) : $stage;
        }
    }
protected function handleStage(&$stages, $stage)
    {
        if ($stage instanceof Pipeline) {
            $stages = array_merge($stages, $stage->stages());
        } else {
            $stages[] = is_callable($stage) ? new Callback($stage) : $stage;
        }
    }
protected function handleStage ( & $ stages , $ stage ) { if ( $ stage instanceof Pipeline ) { $ stages = array_merge ( $ stages , $ stage -> stages ( ) ) ; } else { $ stages [ ] = is_callable ( $ stage ) ? new Callback ( $ stage ) : $ stage ; } }
Handles merging or converting the stage to a callback

@param array                   $stages
@param Pipeline|Stage|callable $stage
Handles merging or converting the stage to a callback