How to: find some component at canvas, on event "component:add"

Hi everyone, let say i've added block <form> on canvas. When i adding next <form> (second time) , need to check: if weather this component already present on canvas, call function implodeComponents(presentedComp, recentlyAddedComp){}

But, On event editor.on('component:add'... i can work only with recently added component. The question is : how to traverse through all components on canvas, to find special component (example <form>) Please look at http://prntscr.com/ij8c82 Thank you , for help.