SublimeText ShowZeroWidthSpace

# http://sublimetext.userecho.com/topic/104394-is-it-possible-to-show-all-characters-spaces-tabs-cr-lf-etc/#comment_180170
import sublime_plugin


class ShowZeroWidthSpace(sublime_plugin.EventListener):
    def on_modified(self, view):
        spaces = []
        p = 0
        while 1:
            s = view.find(u'\u200b', p + 1)
            if not s:
                break
            spaces.append(s)
            p = s.a

        if spaces:
            view.add_regions("zero-width", spaces, "string")
        else:
            view.erase_regions("zero-width")