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seen Apr 20 at 22:20

Apr
17
comment Are there any (free) video formats that include channels for arbitrary time-dependant data?
@MikeBrown, wonderful, thanks!
Mar
25
comment How should I handle database failures in a web application?
@husker, silly question but isn't MVC a bit excessive for such a simple application? I typically associate MVC with big, hulking applications (but I'm very new to the web game...)
Mar
25
comment How should I handle database failures in a web application?
I was hoping for concrete suggestions for how to achieve the behavior you are suggesting. Are there any common design patterns that can be applied to my case, for example?
Mar
25
comment How should I handle database failures in a web application?
@DanPichelman, thanks for your suggested answer. Unfortunately your link doesn't really address my question, which pertains to how I should structure my code to perform all the actions suggested in the answer you indicated (hence the design and architecture tag). I will edit my question to make this clearer!
Feb
21
comment How does the Zope Component Architecture (ZCA) relate to Service Component Architecture (SCA)?
@RobertHarvey, ah okay this seems to be what I was looking for, rather than SOA! Thanks!
Feb
21
comment How does the Zope Component Architecture (ZCA) relate to Service Component Architecture (SCA)?
@RobertHarvey, I'm reasonably familiar with Zope in the context of Twisted. I suppose my question can be rephrased as follows: Is there a common pattern for making use of registered components and utilities? I'm not sure component/utility registration fundamentally differs from using getattr on a submodule, for instance, and I can't even fathom why/how factories necessary or somehow more useful than class __init__ functions and/or metaclasses. The component-registration part of Zope strikes me as reinventing the (module) wheel.
Feb
21
comment How does the Zope Component Architecture (ZCA) relate to Service Component Architecture (SCA)?
@MartijnPieters, Yes, my question is a bit difficult to answer since it amounts to "what am I not understanding?" :) I haven't looked at Plone and Pyramid, but I am familiar with it's use in the Twisted project. I'll look at Plone/Pyramid though, thanks!
Feb
21
comment How does the Zope Component Architecture (ZCA) relate to Service Component Architecture (SCA)?
@MartijnPieters, I would also like to point out that the official Zope site seems to endorse "component architecture" (wiki.zope.org/zope3/ComponentArchitectureOverview) although perhaps this is distinct from SCA? wiki.zope.org/zope3/ComponentArchitectureOverview
Feb
21
comment How does the Zope Component Architecture (ZCA) relate to Service Component Architecture (SCA)?
@MartijnPieters, this surprises me. ZCA seems to have a notion of "services" (in the SCA sense) and is all about making highly-independent things talk to each other through strictly-defined interfaces. Is there a "Zope paradigm" of any sort? Could you address questions 3 and 4? Thanks!
Dec
21
comment How should I represent composeable, associative computations to be repeatedly applied to units of data?
@Giorgio, I wanted to thank amon for his answer, but didn't realize I had to wait 24 hours to attribute the bounty. I wanted to give you some bounty as well, but it seems as though it can't be attributed to comments :/
Dec
21
comment How often is an average programmer expected to reach flow?
@Giorgio, Flow often comes up on the cogsci stackexchange (cogsci.stackexchange.com). It's worth noting, however, that flow has a rather loose definition and is difficult to study as such.
Dec
14
comment How should I represent composeable, associative computations to be repeatedly applied to units of data?
@amon, okay great! I think we're on the same page. Thanks again for your precious help!
Dec
14
comment How should I represent composeable, associative computations to be repeatedly applied to units of data?
@Giorgio, right but here I was talking about the act of composing functions, not the act of applying composed functions to elements in a stream -- apologies if I was unclear! To clarify, the way in which I chain computation c does depend on the way in which computation c-n was performed. Indeed, if a prerequisite operation was not added to the chain, it needs to be added. I was toying with the idea of passing a set object out-of-band via writer monad to carry information about which operations have already been accounted for. Is this clearer?... or am I still missing your point?
Dec
14
comment How should I represent composeable, associative computations to be repeatedly applied to units of data?
@Giorgio, that's essentially correct. More exactly, I never have an operation on input j that depends on the result of an operation on a previous input. I say 'input' because windowed operations are applied to groups of frames, but that's orthogonal to your point. We can indeed treat operations as being independent across inputs.
Dec
14
comment How should I represent composeable, associative computations to be repeatedly applied to units of data?
re your argument against dynamically resolving dependencies during processing: do you think it would be acceptable to resolve dependencies at composition-time? That is, dependencies could be resolved while building the Stream objects and chaining them together, such that everything is in working order when the first Frame instance is passed through the Operation. This could presumably be done by passing a set between Streams when mapping -- a writer monad might be a good way of achieving this. You seem to have some experience in the matter, so I'd love to hear your thoughts.
Dec
14
comment How should I represent composeable, associative computations to be repeatedly applied to units of data?
duly noted! Thanks for the new Google search term :)
Dec
14
comment How should I represent composeable, associative computations to be repeatedly applied to units of data?
I'm so glad you brought this up! Monads seemed to be the correct solution and I've been doing a lot of reading on the subject ... Your answer seems like the missing link between theory and implementation. I'll read it carefully and get back to you, thanks!
Dec
14
comment How should I represent composeable, associative computations to be repeatedly applied to units of data?
@Giorgio, to answer your questions: (1) Yes, I'm defining a fixed operation to each frame. This having been said, it may be relevant to modify the state of the function object based on the contents of a frame, such that subsequent frames will be handled differently. (2-3) My Oi notation is actually quite ambiguous -- I mean that "an operation", O, is preceded and succeeded by other operations. Thus, Oi-n is the operation that happens n operations before Oi. In general, operations can depend on the results of several previous ones (see edits).
Dec
14
comment How should I represent composeable, associative computations to be repeatedly applied to units of data?
@Giorgio, I thought about this solution and did a bunch of reading ("state monad", in particular, got my attention), but I must admit I'm having trouble making the leap from tutorial to implementation. At the very least your comment is reassuring insofar as I'm on the right track -- If you have any specific ideas, I'd be very interested in hearing them.
Dec
12
comment Design pattern for composition workflows
@Alex, Perhaps something like a state monad is what you're after?