http://www.perlmonks.org?node_id=688324


in reply to Re^2: Ways to delete start of string
in thread Ways to delete start of string

If you really want to know, look in pp.c in the perl source, in blead it's in lines 3055 to 3223.

I skimmed it quickly and still have no clue how it does things - too many macros, too little knowledge from my part.