How many lookaheads might be required to decode a single char ?

Property definitions

core $ Codec :: max_lookahead
	# How many lookaheads might be required to decode a single char ?
	fun max_lookahead: Int is abstract
lib/core/codecs/codec_base.nit:51,2--52,35

core $ UTF8Codec :: max_lookahead
	redef fun max_lookahead do return 4
lib/core/codecs/utf8.nit:30,2--36

core $ ISO88591Codec :: max_lookahead
	redef fun max_lookahead do return 1
lib/core/codecs/iso8859_1.nit:28,2--36