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seen Oct 24 at 10:27

Apr
23
comment Ensuring non conflicting components in a modular system
You're talking about building something like a CMS? Then it's up to you really, have a look at Umbraco.com perhaps - one I'm familiar with - it has a component system.
Apr
23
answered Ensuring non conflicting components in a modular system
May
9
awarded  Yearling
Dec
22
awarded  Scholar
Dec
22
accepted Is there a subset of programs that avoid the halting problem
Dec
20
comment Is there a subset of programs that avoid the halting problem
@EricLippert: Did a course on them many years ago - I thought it was one of the most elegant pieces of logic I'd ever come across, though I could never figure out what to do with them. My thinking is coming from the other way - if the universe can't contain infinity, then maybe we're looking at it wrong, what this means though I have no idea.
Dec
20
awarded  Commentator
Dec
20
comment Is there a subset of programs that avoid the halting problem
@S.Lott. Yes you're right - that's interesting, I'll have to reread this stuff. Thanks.
Dec
20
comment Is there a subset of programs that avoid the halting problem
@EricLippert: I'm not sure what my point is at this stage, though it's an interesting discussion. The original question was re the halting problem for finite machines, and that seems to be answered. I'm starting to wonder if there's something more fundamental in the discussion about infinite numbers - they're not realisable in a finite universe. A solution may still be NP hard though. So is there something more fundamental in this in the fact that all numbers we can use are finite no matter how big the computing device.
Dec
20
comment Is there a subset of programs that avoid the halting problem
@EricLippert: But there's still a limit, available memory is a limit, or if you can page out then available disk space is a limit. Nowadays it's a big limit but still a limit. In the absolute limit it's the number of available quantum states in the universe - a fairly large number I'll grant but still a limit.
Dec
19
comment Is there a subset of programs that avoid the halting problem
@S.Lott I mean numbers as represented in a machine, not numbers in the abstract sense. So think of numbers as a fixed number of bits. These numbers have slightly different rules from the integers and reals. Hope that makes sense.
Dec
19
comment Is there a subset of programs that avoid the halting problem
@zvrba That's been on my reading list for some time - probably time to dive in.
Dec
19
comment Is there a subset of programs that avoid the halting problem
@EricLippert again integers are infinite, not as infinite as reals but still infinite. Integers (and reals) are abstractions, what a computer uses are approximations to these. Integers in a machine are bounded to the bit size used to represent them. So any machine that calculates integer values has bounds and so can be determined to halt it seems.
Dec
19
answered Is there a subset of programs that avoid the halting problem
Dec
19
comment Is there a subset of programs that avoid the halting problem
@EricLippert These are interesting problems, but again they operate on the reals which are infinite. If you use the reals as implemented in a machine then you can find if it halts or not it seems. I was thinking more about applications implemented on machines - not proving mathematical theorems.
Dec
19
revised Is there a subset of programs that avoid the halting problem
added 78 characters in body
Dec
19
revised Is there a subset of programs that avoid the halting problem
added 574 characters in body
Dec
19
awarded  Editor
Dec
19
revised Is there a subset of programs that avoid the halting problem
added 423 characters in body
Dec
19
comment Is there a subset of programs that avoid the halting problem
"nearly" is the bit I'm asking. Is there are finite class of problems for which a program can be said to halt and how limited is the problem set? For instance the statement if(i<10) then print(i) does halt for all i. If I restrict the domain of i to 32 bit integers then it too halts.