io.streams.sequence: minor refactor, minor speedup.
io.streams.sequence: minor refactor, minor speedup.

bjourne/factor,mrjbq7/factor,bpollack/factor,bpollack/factor,bpollack/factor,nicolas-p/factor,bjourne/factor,sarvex/factor-lang,factor/factor,dch/factor,AlexIljin/factor,nicolas-p/factor,AlexIljin/factor,dch/factor,tgunr/factor,dch/factor,nicolas-p/factor,mrjbq7/factor,sarvex/factor-lang,factor/factor,nicolas-p/factor,mrjbq7/factor,AlexIljin/factor,bjourne/factor,sarvex/factor-lang,slavapestov/factor,dch/factor,nicolas-p/factor,factor/factor,mrjbq7/factor,sarvex/factor-lang,nicolas-p/factor,dch/factor,AlexIljin/factor,tgunr/factor,mrjbq7/factor,bpollack/factor,slavapestov/factor,slavapestov/factor,slavapestov/factor,tgunr/factor,bpollack/factor,slavapestov/factor,sarvex/factor-lang,nicolas-p/factor,tgunr/factor,bpollack/factor,factor/factor,factor/factor,sarvex/factor-lang,factor/factor,slavapestov/factor,mrjbq7/factor,sarvex/factor-lang,bjourne/factor,AlexIljin/factor,dch/factor,bjourne/factor,AlexIljin/factor,bpollack/factor,bjourne/factor,tgunr/factor,slavapestov/factor,bjourne/factor,AlexIljin/factor,tgunr/factor