+'\A(?:[^\"]++|\"(?:[^\"]*+|\"\")*+\")++'
+ NON QUOTED \"QUOT\"\"ED\" AFTER \"NOT MATCHED
+ 0: NON QUOTED "QUOT""ED" AFTER
+
+'\A(?:[^\"]++|\"(?:[^\"]++|\"\")*+\")++'
+ NON QUOTED \"QUOT\"\"ED\" AFTER \"NOT MATCHED
+ 0: NON QUOTED "QUOT""ED" AFTER
+
+/(?(?!)a|b)/
+ bbb
+ 0: b
+ aaa
+No match
+