Nested Bounded Repetitions causes "Illegal Argument Exception" #952
Description
Running jflex on the following code snippet,
%%
%class search
%standalone
%%
((a|b )*b.{10}){3} {System.out.printf("*** found match");}
And I get the error:
147972 states before minimization, 79107 states in minimized DFA
Old file "search.java" saved as "search.java~"
Writing code to "search.java"
Unexpected exception encountered. This indicates a bug in JFlex.
Please consider filing an issue at http://github.com/jflex-de/jflex/issues/new
character value expected
java.lang.IllegalArgumentException: character value expected
at jflex.generator.PackEmitter.emitUC(PackEmitter.java:105)
at jflex.generator.CountEmitter.emit(CountEmitter.java:116)
at jflex.generator.Emitter.emitDynamicInit(Emitter.java:530)
at jflex.generator.Emitter.emit(Emitter.java:1369)
at jflex.generator.LexGenerator.generate(LexGenerator.java:115)
at jflex.Main.generate(Main.java:320)
at jflex.Main.main(Main.java:336)
As suggested, I report this error.
Can I also ask a question together with this issue report:
I understand that jflex uses the Thompson construction to create an NFA first,
and then determinises it, and minimises the DFA.
I am wondering if these are the main methods for making jflex fast, or are there any
other optimizations involved? Are these methods documented somewhere other
than the user manual? Can someone give a pointer if possible?
Thanks a lot!