fix a bug found by the lexer stress test
fix a bug found by the lexer stress test

Unfortunately, not the bug I was hoping to find.
This bug appears to be very old, however; perhaps
as old as the colorer itself.

mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket