Iterates on the substrings of self if any

Property definitions

core $ Text :: substrings
	# Iterates on the substrings of self if any
	private fun substrings: Iterator[FlatText] is abstract
lib/core/text/abstract_text.nit:81,2--82,55

core $ FlatBuffer :: substrings
	redef fun substrings do return new FlatSubstringsIter(self)
lib/core/text/flat.nit:878,2--60

core $ Concat :: substrings
	redef fun substrings do return new RopeSubstrings.from(self, 0)
lib/core/text/ropes.nit:81,2--64

core $ FlatString :: substrings
	redef fun substrings do return new FlatSubstringsIter(self)
lib/core/text/flat.nit:658,2--60