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A comment on Co-routines as an alternative to state machines.

Re:Co-routines as an alternative to state machines by silentOpen on Saturday August 29, 2009 @02:12PM (#793448)
Why not use mutual recursion and TCO? The function with the program counter is the current state. Problem solved?

Mutable state is your enemy...

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Re:Co-routines as an alternative to state machines by silentbicycle on Saturday August 29, 2009 @04:30PM (#793587)
It's not always just two coroutines (could be thousands), and not every language has TCO.

Also: While mutable state is problematic, sometimes the alternatives are worse.

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Re:Co-routines as an alternative to state machines by silentOpen on Saturday August 29, 2009 @11:20PM (#794008)
That's a good point... mutual recursion lacks dynamism.

The lack of TCO or ability to do mutual recursion+TCO is really the fault of the language. If you have a state machine with a small number (<20) states, mutual recursion seems like a more natural fit (unless you have to have states determined at run-time).

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