Just in time for people realizing that holding onto lots of state is actually a code-design smell and that functional paradigms should be used as much as possible instead!
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OOSMOS, the Object Oriented State Machine Operating System, Is Now Open Source
21–25 of 25 posts
Re: OOSMOS, the Object Oriented State Machine Operating System, Is Now Open Source
#22It amazes me how often programmers can talk about state machines and functions while concurrently pretending that mathematics is, largely, something that either need not be discussed or is of secondary concern.
Re: OOSMOS, the Object Oriented State Machine Operating System, Is Now Open Source
#23Earlier quoted context omitted.
How is a nine-nines reliability record (as achieved, for example, by Erlang http://stackoverflow.com/questions/8426897/erlangs-99-999999... ) not relevant to safety-critical applications? In the second example, you stand on firmer ground though.
Predictable reliability is relevant, certainly. Safety critical systems are frequently hard real-time,[0] by definition resource-constrained. Aspects of functional paradigms are good for safety critical systems, e.g., using pure functions when possible, when it leads to more predictable and testable systems. Recursion and non-strict evaluation, however, are clearly problematic viz. stack consumption, system load, and…
> problematic viz. stack consumption
Not if one codes towards TCO (Tail Call Optimization): http://stackoverflow.com/questions/310974/what-is-tail-call-...
Re: OOSMOS, the Object Oriented State Machine Operating System, Is Now Open Source
#24Just in time for people realizing that holding onto lots of state is actually a code-design smell and that functional paradigms should be used as much as possible instead!
I have done functional programming (FP) with Haskell (including professionally) for years, and I think this notion is misguided. One of the core principles of FP is about state. However, I believe it is to think very carefully about state and be very explicit about how you handle it rather than performing ad-hoc mutations. That often means avoiding state, but many problems require maintaining state. State machines ca…
Thanks for the clarification.
Also, constraint of side effects at the language level allows powerful things like... time-traveling debuggers (does GHC provide anything like this, btw? Because it probably could...)
Re: OOSMOS, the Object Oriented State Machine Operating System, Is Now Open Source
#25Earlier quoted context omitted.
Predictable reliability is relevant, certainly. Safety critical systems are frequently hard real-time,[0] by definition resource-constrained. Aspects of functional paradigms are good for safety critical systems, e.g., using pure functions when possible, when it leads to more predictable and testable systems. Recursion and non-strict evaluation, however, are clearly problematic viz. stack consumption, system load, and…
> problematic viz. stack consumption Not if one codes towards TCO (Tail Call Optimization): http://stackoverflow.com/questions/310974/what-is-tail-call-...
TCO doesn't address unpredictable system load or execution time. Recursion doesn't lead to predictable systems.