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• C++ property system interface for game editors (reflection system)

  - by Cristopher Ismael Sosa Abarca

  I have designed an reusable game engine for an project, and their functionality is like this: Is a completely scripted game engine instead of the usual scripting languages as Lua or Python, this uses Runtime-Compiled C++, and an modified version of Cistron (an component-based programming framework).to be compatible with Runtime-Compiled C++ and so on. Using the typical GameObject and Component classes of the Component-based design pattern, is serializable via JSON, BSON or Binary useful for selecting which objects will be loaded the next time. The main problem: We want to use our custom GameObjects and their components properties in our level editor, before used hardcoded functions to access GameObject base class virtual functions from the derived ones, if do you want to modify an property specifically from that class you need inside into the code, this situation happens too with the derived classes of Component class, in little projects there's no problem but for larger projects becomes tedious, lengthy and error-prone. I've researched a lot to find a solution without luck, i tried with the Ogitor's property system (since our engine is Ogre-based) but we find it inappropiate for the component-based design and it's limited only for the Ogre classes and can lead to performance overhead, and we tried some code we find in the Internet we tested it and worked a little but we considered the macro and lambda abuse too horrible take a look (some code omitted): IWE_IMPLEMENT_PROP_BEGIN(CBaseEntity) IWE_PROP_LEVEL_BEGIN("Editor"); IWE_PROP_INT_S("Id", "Internal id", m_nEntID, [](int n) {}, true); IWE_PROP_LEVEL_END(); IWE_PROP_LEVEL_BEGIN("Entity"); IWE_PROP_STRING_S("Mesh", "Mesh used for this entity", m_pModelName, [pInst](const std::string& sModelName) { pInst->m_stackMemUndoType.push(ENT_MEM_MESH); pInst->m_stackMemUndoStr.push(pInst->getModelName()); pInst->setModel(sModelName, false); pInst->saveState(); }, false); IWE_PROP_VECTOR3_S("Position", m_vecPosition, [pInst](float fX, float fY, float fZ) { pInst->m_stackMemUndoType.push(ENT_MEM_POSITION); pInst->m_stackMemUndoVec3.push(pInst->getPosition()); pInst->saveState(); pInst->m_vecPosition.Get()[0] = fX; pInst->m_vecPosition.Get()[1] = fY; pInst->m_vecPosition.Get()[2] = fZ; pInst->setPosition(pInst->m_vecPosition); }, false); IWE_PROP_QUATERNION_S("Orientation (Quat)", m_quatOrientation, [pInst](float fW, float fX, float fY, float fZ) { pInst->m_stackMemUndoType.push(ENT_MEM_ROTATE); pInst->m_stackMemUndoQuat.push(pInst->getOrientation()); pInst->saveState(); pInst->m_quatOrientation.Get()[0] = fW; pInst->m_quatOrientation.Get()[1] = fX; pInst->m_quatOrientation.Get()[2] = fY; pInst->m_quatOrientation.Get()[3] = fZ; pInst->setOrientation(pInst->m_quatOrientation); }, false); IWE_PROP_LEVEL_END(); IWE_IMPLEMENT_PROP_END() We are finding an simplified way to this, without leading confusing the programmers, (will be released to the public) i find ways to achieve this but they are only available for the common scripting as Lua or editors using C#. also too portable, we can write "wrappers" for different GUI toolkits as Qt or GTK, also i'm thinking to using Boost.Wave to get additional macro functionality without creating my own compiler. The properties designed to use in the editor they are removed in the game since the save file contains their data and loads it using an simple 'load' function to reduce unnecessary code bloat may will be useful if some GameObject property wants to be hidden instead. In summary, there's a way to implement an reflection(property) system for a level editor based in properties from derived classes? Also we can use C++11 and Boost (restricted only to Wave and PropertyTree)

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• Get to Know a Candidate (3 of 25): Virgil Goode&ndash;Constitution Party

  - by Brian Lanham

  DISCLAIMER: This is not a post about “Romney” or “Obama”. This is not a post for whom I am voting. Information sourced for Wikipedia. Meet Virgil Goode of the Constitution Party Goode was served as a Republican member of the United States House of Representatives from 1997 to 2009. He represented the 5th congressional district of Virginia. Goode was born in Richmond, Virginia, the son of Alice Clara (née Besecker) and Virgil Hamlin Goode. He has spent most of his life in Rocky Mount. Goode graduated with a B.A. from the University of Richmond (Phi Beta Kappa) and with a J.D. from the University of Virginia School of Law. He also is a member of Lambda Chi Alpha Fraternity and served in the Army National Guard from 1969 to 1975. Goode grew up as a Democrat. He entered politics soon after graduating from law school. At the age of 27, he won a special election to the state Senate from a Southside district as an independent after the death of the Democratic incumbent. One of his major campaign focuses at the time was advocacy for the Equal Rights Amendment. Soon after being elected, he joined the Democrats. Goode wore his party ties very loosely. He became famous for his support of the tobacco industry, expressing his fear that "his elderly mother would be denied 'the one last pleasure' of smoking a cigarette on her hospital deathbed." He was an ardent defender of gun rights while being an enthusiastic supporter of L. Douglas Wilder, who later became the first elected black governor in the history of the United States. At the Democratic Party's state political convention in 1985, Goode nominated Wilder for lieutenant governor. However, while governor, Wilder cracked down on the sale of guns in the state. After the 1995 elections resulted in a 20–20 split between Democrats and Republicans in the State Senate, Goode seriously considered voting with the Republicans on organizing the chamber. Had he done so, the State Senate would have been under Republican control for the first time since Reconstruction (the Republicans ultimately won control outright in 1999). Goode's actions at the time "forced his party to share power with Republican lawmakers in the state legislature," which further upset the Democratic Party. Goode is on the ballot in CA, FL, ID, IO, LA, MI, MN, MS, MI, NJ, NM, NY, NV, ND, OH, SC, SD, TN, UT, VA, WA, WI, WY.  He is a write-in candidate in CA, CT, DC, GA, IL, IN, ME, MD, MA, MO, NC, TX, VT, WV Constitution Party This party was founded as the “U.S. Taxpayers’ Party” and considers itself conservative. The party's platform is predicated on the principles of the nation's founding documents. The party puts a large focus on immigration, calling for stricter penalties towards illegal immigrants and a moratorium on legal immigration until all federal subsidies to immigrants are discontinued.The party absorbed the American Independent Party, originally founded for George Wallace's 1968 presidential campaign. The American Independent Party of California has been an affiliate of the Constitution Party since its founding; however, current party leadership is disputed and the issue is in court to resolve this conflict. The Constitution Party has some substantial support from the Christian Right and in 2010 achieved major party status in Colorado. Learn more about Virgil Goode and Constitution Party on Wikipedia.

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• Feynman's inbox

  - by user12607414

  Here is Richard Feynman writing on the ease of criticizing theories, and the difficulty of forming them: The problem is not just to say something might be wrong, but to replace it by something — and that is not so easy. As soon as any really definite idea is substituted it becomes almost immediately apparent that it does not work. The second difficulty is that there is an infinite number of possibilities of these simple types. It is something like this. You are sitting working very hard, you have worked for a long time trying to open a safe. Then some Joe comes along who knows nothing about what you are doing, except that you are trying to open the safe. He says ‘Why don’t you try the combination 10:20:30?’ Because you are busy, you have tried a lot of things, maybe you have already tried 10:20:30. Maybe you know already that the middle number is 32 not 20. Maybe you know as a matter of fact that it is a five digit combination… So please do not send me any letters trying to tell me how the thing is going to work. I read them — I always read them to make sure that I have not already thought of what is suggested — but it takes too long to answer them, because they are usually in the class ‘try 10:20:30’. (“Seeking New Laws”, page 161 in The Character of Physical Law.) As a sometime designer (and longtime critic) of widely used computer systems, I have seen similar difficulties appear when anyone undertakes to publicly design a piece of software that may be used by many thousands of customers. (I have been on both sides of the fence, of course.) The design possibilities are endless, but the deep design problems are usually hidden beneath a mass of superfluous detail. The sheer numbers can be daunting. Even if only one customer out of a thousand feels a need to express a passionately held idea, it can take a long time to read all the mail. And it is a fact of life that many of those strong suggestions are only weakly supported by reason or evidence. Opinions are plentiful, but substantive research is time-consuming, and hence rare. A related phenomenon commonly seen with software is bike-shedding, where interlocutors focus on surface details like naming and syntax… or (come to think of it) like lock combinations. On the other hand, software is easier than quantum physics, and the population of people able to make substantial suggestions about software systems is several orders of magnitude bigger than Feynman’s circle of colleagues. My own work would be poorer without contributions — sometimes unsolicited, sometimes passionately urged on me — from the open source community. If a Nobel prize winner thought it was worthwhile to read his mail on the faint chance of learning a good idea, I am certainly not going to throw mine away. (In case anyone is still reading this, and is wondering what provoked a meditation on the quality of one’s inbox contents, I’ll simply point out that the volume has been very high, for many months, on the Lambda-Dev mailing list, where the next version of the Java language is being discussed. Bravo to those of my colleagues who are surfing that wave.) I started this note thinking there was an odd parallel between the life of the physicist and that of a software designer. On second thought, I’ll bet that is the story for anybody who works in public on something requiring special training. (And that would be pretty much anything worth doing.) In any case, Feynman saw it clearly and said it well.

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• Asynchrony in C# 5 (Part II)

  - by javarg

  This article is a continuation of the series of asynchronous features included in the new Async CTP preview for next versions of C# and VB. Check out Part I for more information. So, let’s continue with TPL Dataflow: Asynchronous functions TPL Dataflow Task based asynchronous Pattern Part II: TPL Dataflow Definition (by quote of Async CTP doc): “TPL Dataflow (TDF) is a new .NET library for building concurrent applications. It promotes actor/agent-oriented designs through primitives for in-process message passing, dataflow, and pipelining. TDF builds upon the APIs and scheduling infrastructure provided by the Task Parallel Library (TPL) in .NET 4, and integrates with the language support for asynchrony provided by C#, Visual Basic, and F#.” This means: data manipulation processed asynchronously. “TPL Dataflow is focused on providing building blocks for message passing and parallelizing CPU- and I/O-intensive applications”. Data manipulation is another hot area when designing asynchronous and parallel applications: how do you sync data access in a parallel environment? how do you avoid concurrency issues? how do you notify when data is available? how do you control how much data is waiting to be consumed? etc.  Dataflow Blocks TDF provides data and action processing blocks. Imagine having preconfigured data processing pipelines to choose from, depending on the type of behavior you want. The most basic block is the BufferBlock<T>, which provides an storage for some kind of data (instances of <T>). So, let’s review data processing blocks available. Blocks a categorized into three groups: Buffering Blocks Executor Blocks Joining Blocks Think of them as electronic circuitry components :).. 1. BufferBlock<T>: it is a FIFO (First in First Out) queue. You can Post data to it and then Receive it synchronously or asynchronously. It synchronizes data consumption for only one receiver at a time (you can have many receivers but only one will actually process it). 2. BroadcastBlock<T>: same FIFO queue for messages (instances of <T>) but link the receiving event to all consumers (it makes the data available for consumption to N number of consumers). The developer can provide a function to make a copy of the data if necessary. 3. WriteOnceBlock<T>: it stores only one value and once it’s been set, it can never be replaced or overwritten again (immutable after being set). As with BroadcastBlock<T>, all consumers can obtain a copy of the value. 4. ActionBlock<TInput>: this executor block allows us to define an operation to be executed when posting data to the queue. Thus, we must pass in a delegate/lambda when creating the block. Posting data will result in an execution of the delegate for each data in the queue. You could also specify how many parallel executions to allow (degree of parallelism). 5. TransformBlock<TInput, TOutput>: this is an executor block designed to transform each input, that is way it defines an output parameter. It ensures messages are processed and delivered in order. 6. TransformManyBlock<TInput, TOutput>: similar to TransformBlock but produces one or more outputs from each input. 7. BatchBlock<T>: combines N single items into one batch item (it buffers and batches inputs). 8. JoinBlock<T1, T2, …>: it generates tuples from all inputs (it aggregates inputs). Inputs could be of any type you want (T1, T2, etc.). 9. BatchJoinBlock<T1, T2, …>: aggregates tuples of collections. It generates collections for each type of input and then creates a tuple to contain each collection (Tuple<IList<T1>, IList<T2>>). Next time I will show some examples of usage for each TDF block. * Images taken from Microsoft’s Async CTP documentation.

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• The long road to bug-free software

  - by Tony Davis

  The past decade has seen a burgeoning interest in functional programming languages such as Haskell or, in the Microsoft world, F#. Though still on the periphery of mainstream programming, functional programming concepts are gradually seeping into the imperative C# language (for example, Lambda expressions have their root in functional programming). One of the more interesting concepts from functional programming languages is the use of formal methods, the lofty ideal behind which is bug-free software. The idea is that we write a specification that describes exactly how our function (say) should behave. We then prove that our function conforms to it, and in doing so have proved beyond any doubt that it is free from bugs. All programmers already use one form of specification, specifically their programming language's type system. If a value has a specific type then, in a type-safe language, the compiler guarantees that value cannot be an instance of a different type. Many extensions to existing type systems, such as generics in Java and .NET, extend the range of programs that can be type-checked. Unfortunately, type systems can only prevent some bugs. To take a classic problem of retrieving an index value from an array, since the type system doesn't specify the length of the array, the compiler has no way of knowing that a request for the "value of index 4" from an array of only two elements is "unsafe". We restore safety via exception handling, but the ideal type system will prevent us from doing anything that is unsafe in the first place and this is where we start to borrow ideas from a language such as Haskell, with its concept of "dependent types". If the type of an array includes its length, we can ensure that any index accesses into the array are valid. The problem is that we now need to carry around the length of arrays and the values of indices throughout our code so that it can be type-checked. In general, writing the specification to prove a positive property, even for a problem very amenable to specification, such as a simple sorting algorithm, turns out to be very hard and the specification will be different for every program. Extend this to writing a specification for, say, Microsoft Word and we can see that the specification would end up being no simpler, and therefore no less buggy, than the implementation. Fortunately, it is easier to write a specification that proves that a program doesn't have certain, specific and undesirable properties, such as infinite loops or accesses to the wrong bit of memory. If we can write the specifications to prove that a program is immune to such problems, we could reuse them in many places. The problem is the lack of specification "provers" that can do this without a lot of manual intervention (i.e. hints from the programmer). All this might feel a very long way off, but computing power and our understanding of the theory of "provers" advances quickly, and Microsoft is doing some of it already. Via their Terminator research project they have started to prove that their device drivers will always terminate, and in so doing have suddenly eliminated a vast range of possible bugs. This is a huge step forward from saying, "we've tested it lots and it seems fine". What do you think? What might be good targets for specification and verification? SQL could be one: the cost of a bug in SQL Server is quite high given how many important systems rely on it, so there's a good incentive to eliminate bugs, even at high initial cost. [Many thanks to Mike Williamson for guidance and useful conversations during the writing of this piece] Cheers, Tony.

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• Html.ValidationSummary and Multiple Forms

  - by MightyZot

  Originally posted on: http://geekswithblogs.net/MightyZot/archive/2013/11/11/html.validationsummary-and-multiple-forms.aspxThe Html.ValidationSummary helper writes a div with a list of general errors added to the model state while a request is being serviced. There is generally one form per view or partial view, I think, so often there is only one call to Html.ValidationSummary in the page resulting from the assembly of your views. And, consequently, there is no problem with the markup that Html.ValidationSummary spits out as a result. What if you want to put multiple forms in one view? Even if you create a view model that’s an aggregate of the view models for each form, the error validation summary is going to contain errors from both forms. Check out this screen shot, which shows a page with multiple forms. Notice how the error validation summary shows up twice. Grrr! Errors for the login form also show up in the registration form. Luckily, there is an easy way around this. Pull the errors out of the model state and separate them for each form. You’ll need to identify the appropriate form by setting the key when you make calls to ModelState.AddModelError. Assume in my example that errors for the login form are added to model state using the “LoginForm” key. And, likewise, assume that errors for the registration form are added to model state using the “RegistrationForm” key. An example of that might look like this… // If we got this far, something failed, redisplay form ModelState.AddModelError("LoginForm", "User name or password is not right..."); return View(model); Over in the code for your View, you can pull each form’s errors from the model state using lambda expressions that look like these… var LoginFormErrors = ViewData.ModelState.Where(ms => ms.Key == "LoginForm"); var RegistrationFormErrors = ViewData.ModelState.Where(ms => ms.Key == "RegistrationForm"); Now that you have two collections containing errors, you can display only the errors specific to each form. I’m doing that in my code by removing the calls to Html.ValidationSummary and replacing them with enumerators that look like this… if(LoginFormErrors.Count() > 0) { <div class="cdt-error-list">     <ul>     @foreach (var entry in LoginFormErrors)     {         foreach (var error in entry.Value.Errors)         {             <li>@error.ErrorMessage</li>         }     }     </ul> </div> } …and for the registration form, the code looks like this… @if(RegistrationFormErrors.Count() > 0) { <div class="cdt-error-list">     <ul>     @foreach (var entry in RegistrationFormErrors)     {         foreach (var error in entry.Value.Errors)         {             <li>@error.ErrorMessage</li>         }     }     </ul> </div> } The result is a nice clean separation of the list of errors that are specific to each form. And, this is important because each form is submitted separately in my case, so both forms don’t generate errors in the same context. As you’ll see in the screen shot below, errors added to the model state when the login form is submitted do not show up in the registration form’s validation summary.

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• The long road to bug-free software

  - by Tony Davis

  The past decade has seen a burgeoning interest in functional programming languages such as Haskell or, in the Microsoft world, F#. Though still on the periphery of mainstream programming, functional programming concepts are gradually seeping into the imperative C# language (for example, Lambda expressions have their root in functional programming). One of the more interesting concepts from functional programming languages is the use of formal methods, the lofty ideal behind which is bug-free software. The idea is that we write a specification that describes exactly how our function (say) should behave. We then prove that our function conforms to it, and in doing so have proved beyond any doubt that it is free from bugs. All programmers already use one form of specification, specifically their programming language's type system. If a value has a specific type then, in a type-safe language, the compiler guarantees that value cannot be an instance of a different type. Many extensions to existing type systems, such as generics in Java and .NET, extend the range of programs that can be type-checked. Unfortunately, type systems can only prevent some bugs. To take a classic problem of retrieving an index value from an array, since the type system doesn't specify the length of the array, the compiler has no way of knowing that a request for the "value of index 4" from an array of only two elements is "unsafe". We restore safety via exception handling, but the ideal type system will prevent us from doing anything that is unsafe in the first place and this is where we start to borrow ideas from a language such as Haskell, with its concept of "dependent types". If the type of an array includes its length, we can ensure that any index accesses into the array are valid. The problem is that we now need to carry around the length of arrays and the values of indices throughout our code so that it can be type-checked. In general, writing the specification to prove a positive property, even for a problem very amenable to specification, such as a simple sorting algorithm, turns out to be very hard and the specification will be different for every program. Extend this to writing a specification for, say, Microsoft Word and we can see that the specification would end up being no simpler, and therefore no less buggy, than the implementation. Fortunately, it is easier to write a specification that proves that a program doesn't have certain, specific and undesirable properties, such as infinite loops or accesses to the wrong bit of memory. If we can write the specifications to prove that a program is immune to such problems, we could reuse them in many places. The problem is the lack of specification "provers" that can do this without a lot of manual intervention (i.e. hints from the programmer). All this might feel a very long way off, but computing power and our understanding of the theory of "provers" advances quickly, and Microsoft is doing some of it already. Via their Terminator research project they have started to prove that their device drivers will always terminate, and in so doing have suddenly eliminated a vast range of possible bugs. This is a huge step forward from saying, "we've tested it lots and it seems fine". What do you think? What might be good targets for specification and verification? SQL could be one: the cost of a bug in SQL Server is quite high given how many important systems rely on it, so there's a good incentive to eliminate bugs, even at high initial cost. [Many thanks to Mike Williamson for guidance and useful conversations during the writing of this piece] Cheers, Tony.

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• Detect user logout / shutdown in Python / GTK under Linux

  - by Ivo Wetzel

  OK this is presumably a hard one, I've got an pyGTK application that has random crashes due to X Window errors that I can't catch/control. So I created a wrapper that restarts the app as soon as it detects a crash, now comes the problem, when the user logs out or shuts down the system, the app exits with status 1. But on some X errors it does so too. So I tried literally anything to catch the shutdown/logout, with no success, here's what I've tried: import pygtk import gtk import sys class Test(gtk.Window): def delete_event(self, widget, event, data=None): open("delete_event", "wb") def destroy_event(self, widget, data=None): open("destroy_event", "wb") def destroy_event2(self, widget, event, data=None): open("destroy_event2", "wb") def __init__(self): gtk.Window.__init__(self, gtk.WINDOW_TOPLEVEL) self.show() self.connect("delete_event", self.delete_event) self.connect("destroy", self.destroy_event) self.connect("destroy-event", self.destroy_event2) def foo(): open("add_event", "wb") def ex(): open("sys_event", "wb") from signal import * def clean(sig): f = open("sig_event", "wb") f.write(str(sig)) f.close() exit(0) for sig in (SIGABRT, SIGILL, SIGINT, SIGSEGV, SIGTERM): signal(sig, lambda *args: clean(sig)) def at(): open("at_event", "wb") import atexit atexit.register(at) f = Test() sys.exitfunc = ex gtk.quit_add(gtk.main_level(), foo) gtk.main() open("exit_event", "wb") Not one of these succeeds, is there any low level way to detect the system shutdown? Google didn't find anything related to that. I guess there must be a way, am I right? :/

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• Using M2Crypto to save and load X509 certs in pem files

  - by Brock Pytlik

  I would expect that if I have a X509 cert as an object in memory, saved it as a pem file, then loaded it back in, I would end up with the same cert I started with. This seems not to be the case however. Let's call the original cert A, and the cert loaded from the pem file B. A.as_text() is identical to B.as_text(), but A.as_pem() differs from B.as_pem(). To say the least, I'm confused by this. As a side note, if A has been signed by another entity C, then A will verify against C's cert, but B will not. I've put together a tiny sample program to demonstrate what I'm seeing. When I run this, the second RuntimeError is raised. Thanks, Brock #!/usr/bin/python2.6 import M2Crypto as m2 import time cur_time = m2.ASN1.ASN1_UTCTIME() cur_time.set_time(int(time.time()) - 60*60*24) expire_time = m2.ASN1.ASN1_UTCTIME() # Expire certs in 1 hour. expire_time.set_time(int(time.time()) + 60 * 60 * 24) cs_rsa = m2.RSA.gen_key(1024, 65537, lambda: None) cs_pk = m2.EVP.PKey() cs_pk.assign_rsa(cs_rsa) cs_cert = m2.X509.X509() # These two seem the minimum necessary to make the as_text function call work # at all cs_cert.set_not_before(cur_time) cs_cert.set_not_after(expire_time) # This seems necessary to fill out the complete cert without errors. cs_cert.set_pubkey(cs_pk) # I've tried with the following set lines commented out and not commented. cs_name = m2.X509.X509_Name() cs_name.C = "US" cs_name.ST = "CA" cs_name.OU = "Fake Org CA 1" cs_name.CN = "www.fakeorg.dex" cs_name.Email = "[email protected]" cs_cert.set_subject(cs_name) cs_cert.set_issuer_name(cs_name) cs_cert.sign(cs_pk, md="sha256") orig_text = cs_cert.as_text() orig_pem = cs_cert.as_pem() print "orig_text:\n%s" % orig_text cs_cert.save_pem("/tmp/foo") tcs = m2.X509.load_cert("/tmp/foo") tcs_text = tcs.as_text() tcs_pem = tcs.as_pem() if orig_text != tcs_text: raise RuntimeError( "Texts were different.\nOrig:\n%s\nAfter load:\n%s" % (orig_text, tcs_text)) if orig_pem != tcs_pem: raise RuntimeError( "Pems were different.\nOrig:\n%s\nAfter load:\n%s" % (orig_pem, tcs_pem))

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• ASP NET MVC : "Cannot order by type 'System.Object'."

  - by rah.deex

  This is my code. I got this sample from the Internet and I tried to modify it. private void FillGridData() { //IQueryable<SVC> query = _customerService.GetQueryable(); _dataContext = new dbServiceModelDataContext(); var query = from m in _dataContext.SVCs select m; query = AddQuerySearchCriteria(query, _grid.SearchForm); int totalRows = query.Count(); _grid.Pager.Init(totalRows); if (totalRows == 0) { _grid.Data = new List<SVC>(); return; } query = AddQuerySorting(query, _grid.Sorter); query = AddQueryPaging(query, _grid.Pager); List<SVC> customers = query.ToList(); //***ERROR IN HERE***// _grid.Data = customers; } The error says "Cannot order by type 'System.Object'.", what is the matter? Do you have solution for me? This is The AddQuerySorting Method THE PROBLEM IS IN HERE is there anything wrong about the code? :( private IQueryable<SVC> AddQuerySorting(IQueryable<SVC> query, Sorter sorter) { if (String.IsNullOrEmpty(sorter.SortField)) return query; //Used approach from http://www.singingeels.com/Articles/Self_Sorting_GridView_with_LINQ_Expression_Trees.aspx //instead of a long switch statement var param = Expression.Parameter(typeof(SVC), "customer"); var sortExpression = Expression.Lambda<Func<SVC, object>> (Expression.Convert(Expression.Property(param, sorter.SortField), typeof(object)), param); if (sorter.SortDirection == SortDirection.Asc) query = query.OrderBy(sortExpression); else query = query.OrderByDescending(sortExpression); return query; } here is AddQueryPaging Method private IQueryable<SVC> AddQueryPaging(IQueryable<SVC> query, Pager pager) { if (pager.TotalPages == 0) return query; query = query.Skip((pager.CurrentPage - 1) * pager.PageSize) .Take(pager.PageSize); return query; }

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• Rspec2, Rails3, Authlogic: Can't run specs

  - by Sam

  When I do rspec spec in my rails project, I get No examples were matched. Perhaps {:if=>#<Proc:0x0000010126e998@/Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/configuration.rb:50 (lambda)>, :unless=>#<Proc:0x0000010126e970@/Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/configuration.rb:51 (lambda)>} is excluding everything? Finished in 0.00004 seconds 0 examples, 0 failures Now, this seems like maybe if I wrote a spec it would work, but as soon as I write a spec (and I do include spec_helper) /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/backward_compatibility.rb:20:in `const_missing': uninitialized constant Authlogic (NameError) from /{myapp}/app/models/user_session.rb:1:in `<top (required)>' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/engine.rb:138:in `block (2 levels) in eager_load!' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/engine.rb:137:in `each' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/engine.rb:137:in `block in eager_load!' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/engine.rb:135:in `each' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/engine.rb:135:in `eager_load!' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/application.rb:108:in `eager_load!' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/application/finisher.rb:41:in `block in <module:Finisher>' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/initializable.rb:25:in `instance_exec' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/initializable.rb:25:in `run' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/initializable.rb:50:in `block in run_initializers' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/initializable.rb:49:in `each' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/initializable.rb:49:in `run_initializers' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/application.rb:134:in `initialize!' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/railties-3.0.3/lib/rails/application.rb:77:in `method_missing' from /{myapp}/config/environment.rb:5:in `<top (required)>' from <internal:lib/rubygems/custom_require>:29:in `require' from <internal:lib/rubygems/custom_require>:29:in `require' from /{myapp}/spec/spec_helper.rb:3:in `<top (required)>' from <internal:lib/rubygems/custom_require>:29:in `require' from <internal:lib/rubygems/custom_require>:29:in `require' from /{myapp}/spec/controllers/pages_controller_spec.rb:1:in `<top (required)>' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/configuration.rb:388:in `load' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/configuration.rb:388:in `block in load_spec_files' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/configuration.rb:388:in `map' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/configuration.rb:388:in `load_spec_files' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/command_line.rb:18:in `run' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/runner.rb:55:in `run_in_process' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/runner.rb:46:in `run' from /Users/samliu/.rvm/gems/ruby-1.9.2-p0@rails3/gems/rspec-core-2.3.1/lib/rspec/core/runner.rb:10:in `block in autorun' The important line here seems to be /core/backward_compatibility.rb:20:in `const_missing': uninitialized constant Authlogic (NameError) Now if this were rails 2.3.8, I'd simply put config.gem "authlogic" into the environment.rb, in the initialization code block. However, the rails 3 environment.rb looks way different (there is no config code block, so putting it in arbitrarily causes an error where config is not defined). So my questions are 1) Do I actually have to put the gem config anywhere? I looked at https://github.com/trevmex/authlogic_rails3_example/ and it seems he didn't put it anywhere. 2) Does anyone know what I'm doing wrong in terms of rspec? My gem list is *** LOCAL GEMS *** abstract (1.0.0) actionmailer (3.0.3, 3.0.1, 3.0.0, 3.0.0.rc2, 2.3.4) actionpack (3.0.3, 3.0.1, 3.0.0, 3.0.0.rc2, 2.3.4) activemodel (3.0.3, 3.0.1, 3.0.0, 3.0.0.rc2) activerecord (3.0.3, 3.0.1, 3.0.0, 3.0.0.rc2, 2.3.4) activeresource (3.0.3, 3.0.1, 3.0.0, 3.0.0.rc2, 2.3.4) activesupport (3.0.3, 3.0.1, 3.0.0, 3.0.0.rc2, 2.3.4) arel (2.0.6, 1.0.1) asdf (0.5.0) authlogic (2.1.6, 2.1.3) autotest (4.4.6, 4.4.1) autotest-fsevent (0.2.4) autotest-growl (0.2.9) autotest-rails (4.1.0) autotest-rails-pure (4.1.2) bluecloth (2.0.9) builder (2.1.2) bundler (1.0.7, 1.0.2) cgi_multipart_eof_fix (2.5.0) commonwatir (1.6.2) couchrest (0.33) cri (1.0.1) cucumber (0.4.4, 0.4.3, 0.3.11) daemons (1.1.0, 1.0.10) dependencies (0.0.7) diff-lcs (1.1.2) erubis (2.6.6) fastercsv (1.5.0) fastthread (1.0.7) firewatir (1.6.2) flay (1.4.0) flog (2.2.0) funfx (0.2.2) gem_plugin (0.2.3) gemsonrails (0.7.2) giraffesoft-resource_controller (0.6.5) haml (2.2.14) hoe (2.3.3) i18n (0.4.1) jscruggs-metric_fu (1.1.5) json_pure (1.1.9) kramdown (0.12.0) mail (2.2.13, 2.2.6.1) memcache-client (1.8.5) mime-types (1.16) mojombo-chronic (0.3.0) mongrel (1.1.5) monk (0.0.7) nanoc (3.1.5) nanoc3 (3.1.5) nokogiri (1.4.3.1, 1.4.0) open4 (0.9.6) polyglot (0.3.1, 0.2.9) rack (1.2.1, 1.0.1) rack-mount (0.6.13) rack-test (0.5.6) rails (3.0.0, 2.3.4) rails3-generators (0.17.0, 0.14.0) railties (3.0.3, 3.0.1, 3.0.0, 3.0.0.rc2) rake (0.8.7) relevance-rcov (0.9.2.1) rest-client (1.0.3) rspec (2.3.0, 2.0.0.rc, 1.2.9) rspec-core (2.3.1, 2.0.0.rc) rspec-expectations (2.3.0, 2.0.0.rc) rspec-mocks (2.3.0, 2.0.0.rc) rspec-rails (2.3.1, 2.0.0.rc, 1.2.9) ruby_parser (2.0.4) rubyforge (2.0.3) rubygems-update (1.3.6, 1.3.5) rvm (1.0.13) s4t-utils (1.0.4) safariwatir (0.3.7) sexp_processor (3.0.3) spork (0.7.3) sqlite3-ruby (1.3.1, 1.2.5) sys-uname (0.8.5) term-ansicolor (1.0.4) text-format (1.0.0) text-hyphen (1.0.0) thor (0.14.6, 0.14.3, 0.12.0) treetop (1.4.8, 1.4.2) tzinfo (0.3.23) user-choices (1.1.6) vlad (2.0.0) vlad-git (2.1.0) webrat (0.7.1, 0.6.0, 0.5.3) xml-simple (1.0.12) ZenTest (4.4.2) I am using ruby 1.9.2 and rails 3.0.3 installed using RVM on OSX 10.6 Snow Leopard. I just want to be able to run my specs like I used to. As a separate issue, autotest yields an error about an include for autotest/growl but I installed autotest-growl. Maybe this is a gem issue? I tried doing the same things and get the same error when it comes to using my ubuntu 10.04 server machine though. Gemfile source 'http://rubygems.org' gem 'rails', '3.0.3' # Bundle edge Rails instead: # gem 'rails', :git => 'git://github.com/rails/rails.git' gem 'sqlite3-ruby', :require => 'sqlite3' group :couch do gem 'couchrest' end group :user_auth do gem 'authlogic' gem "rails3-generators" gem 'facebooker' end group :markup do gem 'haml' gem 'sass' end group :testing do gem 'rspec-rails' gem 'rspec' gem 'webrat' gem 'cucumber' gem 'capybara' gem 'factory_girl' gem 'shoulda' gem 'autotest' end group :server do gem 'unicorn' end # Use unicorn as the web server # gem 'unicorn' # Deploy with Capistrano # gem 'capistrano' # To use debugger # gem 'ruby-debug' # Bundle the extra gems: # gem 'bj' # gem 'nokogiri' # gem 'sqlite3-ruby', :require => 'sqlite3' # gem 'aws-s3', :require => 'aws/s3' # Bundle gems for the local environment. Make sure to # put test-only gems in this group so their generators # and rake tasks are available in development mode: # group :development, :test do # gem 'webrat' # end Gemfile.lock GEM remote: http://rubygems.org/ specs: ZenTest (4.4.2) abstract (1.0.0) actionmailer (3.0.3) actionpack (= 3.0.3) mail (~> 2.2.9) actionpack (3.0.3) activemodel (= 3.0.3) activesupport (= 3.0.3) builder (~> 2.1.2) erubis (~> 2.6.6) i18n (~> 0.4) rack (~> 1.2.1) rack-mount (~> 0.6.13) rack-test (~> 0.5.6) tzinfo (~> 0.3.23) activemodel (3.0.3) activesupport (= 3.0.3) builder (~> 2.1.2) i18n (~> 0.4) activerecord (3.0.3) activemodel (= 3.0.3) activesupport (= 3.0.3) arel (~> 2.0.2) tzinfo (~> 0.3.23) activeresource (3.0.3) activemodel (= 3.0.3) activesupport (= 3.0.3) activesupport (3.0.3) arel (2.0.6) authlogic (2.1.6) activesupport autotest (4.4.6) ZenTest (>= 4.4.1) builder (2.1.2) capybara (0.4.0) celerity (>= 0.7.9) culerity (>= 0.2.4) mime-types (>= 1.16) nokogiri (>= 1.3.3) rack (>= 1.0.0) rack-test (>= 0.5.4) selenium-webdriver (>= 0.0.27) xpath (~> 0.1.2) celerity (0.8.6) childprocess (0.1.6) ffi (~> 0.6.3) couchrest (1.0.1) json (>= 1.4.6) mime-types (>= 1.15) rest-client (>= 1.5.1) cucumber (0.10.0) builder (>= 2.1.2) diff-lcs (~> 1.1.2) gherkin (~> 2.3.2) json (~> 1.4.6) term-ansicolor (~> 1.0.5) culerity (0.2.13) diff-lcs (1.1.2) erubis (2.6.6) abstract (>= 1.0.0) facebooker (1.0.75) json_pure (>= 1.0.0) factory_girl (1.3.2) ffi (0.6.3) rake (>= 0.8.7) gherkin (2.3.2) json (~> 1.4.6) term-ansicolor (~> 1.0.5) haml (3.0.25) i18n (0.5.0) json (1.4.6) json_pure (1.4.6) kgio (2.0.0) mail (2.2.13) activesupport (>= 2.3.6) i18n (>= 0.4.0) mime-types (~> 1.16) treetop (~> 1.4.8) mime-types (1.16) nokogiri (1.4.4) polyglot (0.3.1) rack (1.2.1) rack-mount (0.6.13) rack (>= 1.0.0) rack-test (0.5.6) rack (>= 1.0) rails (3.0.3) actionmailer (= 3.0.3) actionpack (= 3.0.3) activerecord (= 3.0.3) activeresource (= 3.0.3) activesupport (= 3.0.3) bundler (~> 1.0) railties (= 3.0.3) rails3-generators (0.17.0) railties (>= 3.0.0) railties (3.0.3) actionpack (= 3.0.3) activesupport (= 3.0.3) rake (>= 0.8.7) thor (~> 0.14.4) rake (0.8.7) rest-client (1.6.1) mime-types (>= 1.16) rspec (2.3.0) rspec-core (~> 2.3.0) rspec-expectations (~> 2.3.0) rspec-mocks (~> 2.3.0) rspec-core (2.3.1) rspec-expectations (2.3.0) diff-lcs (~> 1.1.2) rspec-mocks (2.3.0) rspec-rails (2.3.1) actionpack (~> 3.0) activesupport (~> 3.0) railties (~> 3.0) rspec (~> 2.3.0) rubyzip (0.9.4) sass (3.1.0.alpha.206) selenium-webdriver (0.1.2) childprocess (~> 0.1.5) ffi (~> 0.6.3) json_pure rubyzip shoulda (2.11.3) sqlite3-ruby (1.3.2) term-ansicolor (1.0.5) thor (0.14.6) treetop (1.4.9) polyglot (>= 0.3.1) tzinfo (0.3.23) unicorn (3.1.0) kgio (~> 2.0.0) rack webrat (0.7.2) nokogiri (>= 1.2.0) rack (>= 1.0) rack-test (>= 0.5.3) xpath (0.1.2) nokogiri (~> 1.3) PLATFORMS ruby DEPENDENCIES authlogic autotest capybara couchrest cucumber facebooker factory_girl haml rails (= 3.0.3) rails3-generators rspec rspec-rails sass shoulda sqlite3-ruby unicorn webrat

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• VB .NET DirectCast and Type Reflection

  - by msarchet

  The application that I am working on has a generic Parent Form called RSChild, that is used to perform some operations depending on whether or not the control that is contained within it is in a MdiTabManager or inside of its own modal form. Then the actual User Controls contained within Inherit from a Interface Called ObjectEdit (Objects that we allow to be edited). At a point in my code I am doing this. Public Function doesTabExist(ByVal id As Integer, ByVal recordType As Enums.eRecordType) As Boolean Dim alikePages As Object = (From tabs In DirectCast(Control.FromHandle(MainForm.SharedHandle), MainForm).XtraTabbedMdiManager1.Pages Where DirectCast(tabs.MdiChild, RSChild).RSObject.RecordType = recordType Select tabs) For Each page As DevExpress.XtraTabbedMdi.XtraMdiTabPage In alikePages Select Case recordType Case Enums.eRecordType.Doctor If id = DirectCast(castTabPageToRSChild(page).RSObject, UI.Doctor).ID Then pageToActive(page) Return True End If 'rest of the cases so the case block is repeated 10 times' End Function And my castTabPageToRSChild(page) is a lambda function as Such Dim castTabPageToRSChild As Func(Of DevExpress.XtraTabbedMdi.XtraMdiTabPage, RSChild) = Function(page) DirectCast(page.MdiChild, RSChild) So my Question is, I have about 10 case statements, all because I can't seem to find a way to use reflection to get the underlying Type of the RSObject Object. So I have the whole If block repeated over and over. I tried doing castTabPageToRSChild(page)RSObject.GetType and using that in the DirectCast and I also tried creating another object that was separate from that and doing the same thing. My code works as intended I'm just trying to see if there is a manner in which I didn't have a lot of replicated code. My vision would be to do something like For Each page As XtraMdiTabPage In alikePages If id = DirectCast(castTabPageToRSchild(page).RSObject, TypeOfThatObject).Id Then Return True Next However I have a feeling this is not possible due to the behavior of DirectCast.

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• Mercurial fails while commiting/updating/etc. using Mercuriual+TrueCrypt+MAC

  - by lukewar

  While trying to work with Mercurial on project located on TrueCrypt partition I always get en error as follows: ** unknown exception encountered, details follow ** report bug details to http://mercurial.selenic.com/bts/ ** or [email protected] ** Mercurial Distributed SCM (version 1.5.2+20100502) ** Extensions loaded: Traceback (most recent call last): File "/usr/local/bin/hg", line 27, in mercurial.dispatch.run() File "/Library/Python/2.6/site-packages/mercurial/dispatch.py", line 16, in run sys.exit(dispatch(sys.argv[1:])) File "/Library/Python/2.6/site-packages/mercurial/dispatch.py", line 30, in dispatch return _runcatch(u, args) File "/Library/Python/2.6/site-packages/mercurial/dispatch.py", line 50, in _runcatch return _dispatch(ui, args) File "/Library/Python/2.6/site-packages/mercurial/dispatch.py", line 470, in _dispatch return runcommand(lui, repo, cmd, fullargs, ui, options, d) File "/Library/Python/2.6/site-packages/mercurial/dispatch.py", line 340, in runcommand ret = _runcommand(ui, options, cmd, d) File "/Library/Python/2.6/site-packages/mercurial/dispatch.py", line 521, in _runcommand return checkargs() File "/Library/Python/2.6/site-packages/mercurial/dispatch.py", line 475, in checkargs return cmdfunc() File "/Library/Python/2.6/site-packages/mercurial/dispatch.py", line 469, in d = lambda: util.checksignature(func)(ui, *args, **cmdoptions) File "/Library/Python/2.6/site-packages/mercurial/util.py", line 401, in check return func(*args, **kwargs) File "/Library/Python/2.6/site-packages/mercurial/commands.py", line 3332, in update return hg.update(repo, rev) File "/Library/Python/2.6/site-packages/mercurial/hg.py", line 362, in update stats = _merge.update(repo, node, False, False, None) File "/Library/Python/2.6/site-packages/mercurial/merge.py", line 495, in update _checkunknown(wc, p2) File "/Library/Python/2.6/site-packages/mercurial/merge.py", line 77, in _checkunknown for f in wctx.unknown(): File "/Library/Python/2.6/site-packages/mercurial/context.py", line 660, in unknown return self._status[4] File "/Library/Python/2.6/site-packages/mercurial/util.py", line 156, in get result = self.func(obj) File "/Library/Python/2.6/site-packages/mercurial/context.py", line 622, in _status return self._repo.status(unknown=True) File "/Library/Python/2.6/site-packages/mercurial/localrepo.py", line 1023, in status if (f not in ctx1 or ctx2.flags(f) != ctx1.flags(f) File "/Library/Python/2.6/site-packages/mercurial/context.py", line 694, in flags flag = findflag(self._parents[0]) File "/Library/Python/2.6/site-packages/mercurial/context.py", line 690, in findflag return ff(path) File "/Library/Python/2.6/site-packages/mercurial/dirstate.py", line 145, in f if 'x' in fallback(x): TypeError: argument of type 'NoneType' is not iterable It is worth mention that Mercurial works perfectly if project is not located on TrueCrypt partition. Configuration: MacOS X 10.6.3 Mercurial Distributed SCM (version 1.5.2+20100502) Python 2.6.5 Have anyone of you generous people able to help me? :)

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• Images missing after moving Django to new server

  - by miszczu

  I'm moving Django project to new server. I'm newbie in Django, and I don't know where should be upload folder. There are all images which should be displayed on website. In config file I haven't seen upload folder I could specify, so I'm guessing it always should be the same location for django projects or I just can't find it. Locations are saved in database. When I've put uploaded files into media folder, so url was like domain.co.uk/media/upload/media/images/year/month/day/image_name.ext and the same is on the old website, images on website ware still missing. All images are visible if I put url by hand, but django doesn't seems to see files. Also I check django log file: 2012-05-30 09:13:33,393 ERROR render: Thumbnail tag failed: [in /usr/lib/python2.6/site-packages/sorl_thumbnail-11.12-py2.6.egg/sorl/thumbnail/templatetags/thumbnail.py (line 49)] Traceback (most recent call last): File "/usr/lib/python2.6/site-packages/sorl_thumbnail-11.12-py2.6.egg/sorl/thumbnail/templatetags/thumbnail.py", line 45, in render return self._render(context) File "/usr/lib/python2.6/site-packages/sorl_thumbnail-11.12-py2.6.egg/sorl/thumbnail/templatetags/thumbnail.py", line 97, in _render file_, geometry, **options File "/usr/lib/python2.6/site-packages/sorl_thumbnail-11.12-py2.6.egg/sorl/thumbnail/base.py", line 50, in get_thumbnail cached = default.kvstore.get(thumbnail) File "/usr/lib/python2.6/site-packages/sorl_thumbnail-11.12-py2.6.egg/sorl/thumbnail/kvstores/base.py", line 25, in get return self._get(image_file.key) File "/usr/lib/python2.6/site-packages/sorl_thumbnail-11.12-py2.6.egg/sorl/thumbnail/kvstores/base.py", line 123, in _get value = self._get_raw(add_prefix(key, identity)) File "/usr/lib/python2.6/site-packages/sorl_thumbnail-11.12-py2.6.egg/sorl/thumbnail/kvstores/cached_db_kvstore.py", line 26, in _get_raw value = KVStoreModel.objects.get(key=key).value File "/usr/lib/python2.6/site-packages/django/db/models/manager.py", line 132, in get return self.get_query_set().get(*args, **kwargs) File "/usr/lib/python2.6/site-packages/django/db/models/query.py", line 344, in get num = len(clone) File "/usr/lib/python2.6/site-packages/django/db/models/query.py", line 82, in __len__ self._result_cache = list(self.iterator()) File "/usr/lib/python2.6/site-packages/django/db/models/query.py", line 273, in iterator for row in compiler.results_iter(): File "/usr/lib/python2.6/site-packages/django/db/models/sql/compiler.py", line 680, in results_iter for rows in self.execute_sql(MULTI): File "/usr/lib/python2.6/site-packages/django/db/models/sql/compiler.py", line 735, in execute_sql cursor.execute(sql, params) File "/usr/lib/python2.6/site-packages/django/db/backends/util.py", line 34, in execute return self.cursor.execute(sql, params) File "/usr/lib/python2.6/site-packages/django/db/backends/mysql/base.py", line 86, in execute return self.cursor.execute(query, args) File "/usr/lib64/python2.6/site-packages/MySQLdb/cursors.py", line 174, in execute self.errorhandler(self, exc, value) File "/usr/lib64/python2.6/site-packages/MySQLdb/connections.py", line 36, in defaulterrorhandler raise errorclass, errorvalue DatabaseError: (1146, "Table 'thumbnail_kvstore' doesn't exist") 2012-05-30 09:13:33,396 DEBUG execute: (0.000) SELECT `freetext_freetext`.`id`, `freetext_freetext`.`key`, `freetext_freetext`.`content`, `freetext_freetext`.`active` FROM `freetext_freetext` WHERE (`freetext_freetext`.`active` = True AND `freetext_freetext`.`key` = office-closed-message ); args=(True, u'office-closed-message') [in /usr/lib/python2.6/site-packages/django/db/backends/util.py (line 44)] 2012-05-30 09:13:33,399 DEBUG execute: (0.000) SELECT `menus_menu`.`id`, `menus_menu`.`name`, `menus_menu`.`slug`, `menus_menu`.`base_url`, `menus_menu`.`description`, `menus_menu`.`enabled` FROM `menus_menu` WHERE (`menus_menu`.`enabled` = True AND `menus_menu`.`slug` = about ); args=(True, u'about') [in /usr/lib/python2.6/site-packages/django/db/backends/util.py (line 44)] 2012-05-30 09:13:33,401 DEBUG execute: (0.000) SELECT `menus_menuitem`.`id`, `menus_menuitem`.`menu_id`, `menus_menuitem`.`title`, `menus_menuitem`.`url`, `menus_menuitem`.`order` FROM `menus_menuitem` INNER JOIN `menus_menu` ON (`menus_menuitem`.`menu_id` = `menus_menu`.`id`) WHERE `menus_menu`.`slug` = about ORDER BY `menus_menuitem`.`order` ASC; args=(u'about',) [in /usr/lib/python2.6/site-packages/django/db/backends/util.py (line 44)] 2012-05-30 09:13:33,404 DEBUG execute: (0.000) SELECT `freetext_freetext`.`id`, `freetext_freetext`.`key`, `freetext_freetext`.`content`, `freetext_freetext`.`active` FROM `freetext_freetext` WHERE (`freetext_freetext`.`active` = True AND `freetext_freetext`.`key` = contactdetails-footer ); args=(True, u'contactdetails-footer') [in /usr/lib/python2.6/site-packages/django/db/backends/util.py (line 44)] I checked database and there is no table calls thumbnail_kvstore, but I have database backup, and in backup files this table doesn't exist. All uploaded files I get are in media/uploads/media/. Also I'm getting errors on some pages: Syntax error. Expected: ``thumbnail source geometry [key1=val1 key2=val2...] as var`` /usr/lib/python2.6/site-packages/sorl_thumbnail-11.12-py2.6.egg/sorl/thumbnail/templatetags/thumbnail.py in __init__, line 72 In template /var/www/vhosts/domain.co.uk/sites/apps/shop/products/templates/products/product_detail.html, error at line 34 {% thumbnail image.file "800x700" detail as zoom %} Maybe some modules I install are not in the right version. Dont know how to fix it. Im using, CentOS 6, mod_wsgi, apache, python 2.6. Update 1.0: On the old server was Django 1.3, on the new one is Django 1.3.1 Update 1.1: I this i know where is the problem. I tried python manage.py syncdb and this is output: Syncing... Creating tables ... The following content types are stale and need to be deleted: orders | ordercontact Any objects related to these content types by a foreign key will also be deleted. Are you sure you want to delete these content types? If you're unsure, answer 'no'. Type 'yes' to continue, or 'no' to cancel: no Installing custom SQL ... Installing indexes ... No fixtures found. Synced: > django.contrib.auth > django.contrib.contenttypes > django.contrib.sessions > django.contrib.sites > django.contrib.messages > django.contrib.admin > django.contrib.admindocs > django.contrib.markup > django.contrib.sitemaps > django.contrib.redirects > django_filters > freetext > sorl.thumbnail > django_extensions > south > currencies > pagination > tagging > honeypot > core > faq > logentry > menus > news > shop > shop.cart > shop.orders Not synced (use migrations): - dbtemplates - contactform - links - media - pages - popularity - testimonials - shop.brands - shop.collections - shop.discount - shop.pricing - shop.product_types - shop.products - shop.shipping - shop.tax (use ./manage.py migrate to migrate these) Next I run python manage.py migrate, and thats what i get: Running migrations for dbtemplates: - Migrating forwards to 0002_auto__del_unique_template_name. > dbtemplates:0001_initial ! Error found during real run of migration! Aborting. ! Since you have a database that does not support running ! schema-altering statements in transactions, we have had ! to leave it in an interim state between migrations. ! You *might* be able to recover with: = DROP TABLE `django_template` CASCADE; [] = DROP TABLE `django_template_sites` CASCADE; [] ! The South developers regret this has happened, and would ! like to gently persuade you to consider a slightly ! easier-to-deal-with DBMS. ! NOTE: The error which caused the migration to fail is further up. Traceback (most recent call last): File "manage.py", line 13, in <module> execute_manager(settings) File "/usr/lib/python2.6/site-packages/django/core/management/__init__.py", line 438, in execute_manager utility.execute() File "/usr/lib/python2.6/site-packages/django/core/management/__init__.py", line 379, in execute self.fetch_command(subcommand).run_from_argv(self.argv) File "/usr/lib/python2.6/site-packages/django/core/management/base.py", line 191, in run_from_argv self.execute(*args, **options.__dict__) File "/usr/lib/python2.6/site-packages/django/core/management/base.py", line 220, in execute output = self.handle(*args, **options) File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/management/commands/migrate.py", line 105, in handle ignore_ghosts = ignore_ghosts, File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/migration/__init__.py", line 191, in migrate_app success = migrator.migrate_many(target, workplan, database) File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/migration/migrators.py", line 221, in migrate_many result = migrator.__class__.migrate_many(migrator, target, migrations, database) File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/migration/migrators.py", line 292, in migrate_many result = self.migrate(migration, database) File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/migration/migrators.py", line 125, in migrate result = self.run(migration) File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/migration/migrators.py", line 99, in run return self.run_migration(migration) File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/migration/migrators.py", line 81, in run_migration migration_function() File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/migration/migrators.py", line 57, in <lambda> return (lambda: direction(orm)) File "/usr/lib/python2.6/site-packages/django_dbtemplates-1.3-py2.6.egg/dbtemplates/migrations/0001_initial.py", line 18, in forwards ('last_changed', self.gf('django.db.models.fields.DateTimeField')(default=datetime.datetime.now)), File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/db/generic.py", line 226, in create_table ', '.join([col for col in columns if col]), File "/usr/lib/python2.6/site-packages/South-0.7.3-py2.6.egg/south/db/generic.py", line 150, in execute cursor.execute(sql, params) File "/usr/lib/python2.6/site-packages/django/db/backends/util.py", line 34, in execute return self.cursor.execute(sql, params) File "/usr/lib/python2.6/site-packages/django/db/backends/mysql/base.py", line 86, in execute return self.cursor.execute(query, args) File "/usr/lib64/python2.6/site-packages/MySQLdb/cursors.py", line 174, in execute self.errorhandler(self, exc, value) File "/usr/lib64/python2.6/site-packages/MySQLdb/connections.py", line 36, in defaulterrorhandler raise errorclass, errorvalue _mysql_exceptions.OperationalError: (1050, "Table 'django_template' already exists") Also i run python manage.py migrate --list, and uotput is: dbtemplates (*) 0001_initial (*) 0002_auto__del_unique_template_name contactform (*) 0001_initial (*) 0002_auto__add_callback (*) 0003_auto__add_field_callback_notes (*) 0004_auto__add_field_callback_is_closed__add_field_callback_closed (*) 0005_auto__add_field_callback_url (*) 0006_auto__add_contact (*) 0007_auto__add_field_contact_category (*) 0008_auto__add_field_contact_url links (*) 0001_initial (*) 0002_auto__add_field_category_enabled__add_field_category_order media (*) 0001_initial (*) 0002_auto__del_field_image_external_url__add_field_image_link_url__del_fiel (*) 0003_add_model_FileAttachment (*) 0004_auto__chg_field_file_slug__chg_field_image_slug (*) 0005_auto__chg_field_image_file (*) 0006_auto__chg_field_file_file pages (*) 0001_initial (*) 0002_auto__chg_field_page_meta_description__chg_field_page_meta_title__chg_ (*) 0003_auto__add_field_page_show_in_sitemap (*) 0004_auto__add_field_page_changefreq__add_field_page_priority popularity (*) 0001_initial testimonials (*) 0001_initial (*) 0002_auto__add_field_testimonial_is_featured brands (*) 0001_initial (*) 0002_auto__add_field_brand_template (*) 0003_auto__chg_field_brand_meta_description__chg_field_brand_meta_title__ch (*) 0004_auto__add_field_brand_url (*) 0005_auto__del_field_brand_image__add_field_brand_logo collections (*) 0001_initial (*) 0002_auto__add_field_collection_discount (*) 0003_auto__chg_field_collection_meta_description__chg_field_collection_meta (*) 0004_auto__add_field_collection_is_featured (*) 0005_auto__add_field_collection_order discount (*) 0001_initial (*) 0002_added_field_discount_description (*) 0003_auto__add_field_discountvoucher_automatic (*) 0004_auto__add_field_discountvoucher_collection (*) 0005_auto__del_field_discountvoucher_collection (*) 0006_auto__chg_field_discountvoucher_expiry_date pricing (*) 0001_initial (*) 0002_auto__add_pricingrule product_types (*) 0001_initial (*) 0002_auto__add_field_producttype_meta_title__add_field_producttype_meta_des (*) 0003_auto__add_field_producttype_summary__add_field_producttype_description products (*) 0001_initial (*) 0002_auto__del_field_product_is_featured (*) 0003_auto__chg_field_product_meta_keywords__chg_field_product_meta_descript (*) 0004_auto shipping (*) 0001_initial (*) 0002_auto__add_field_shippingmethod_includes_tax__add_field_shippingmethod_ (*) 0003_auto__add_field_shippingmethod_order (*) 0004_auto__del_field_shippingmethod_tax_rate__del_field_shippingmethod_incl (*) 0005_auto__del_field_shippingrule_enabled tax (*) 0001_initial (*) 0002_auto__add_field_taxrate_internal_name (*) 0003_initial_internal_names (*) 0004_auto__add_unique_taxrate_internal_name (*) 0005_force_unique_taxrate_name (*) 0006_auto__add_unique_taxrate_name After that some images source were something like this: src="cache/1e/bd/1ebd719910aa843238028edd5fe49e71.jpg" Is any1 could help me with syncdb pledase?

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• Python: speed up removal of every n-th element from list.

  - by ChristopheD

  I'm trying to solve this programming riddle and althought the solution (see code below) works correct, it is too slow for succesful submission. Any pointers as how to make this run faster? (removal of every n-th element from a list)? Or suggestions for a better algorithm to calculate the same; seems I can't think of anything else then brute-force for now... Basically the task at hand is: GIVEN: L = [2,3,4,5,6,7,8,9,10,11,........] 1. Take the first remaining item in list L (in the general case 'n'). Move it to the 'lucky number list'. Then drop every 'n-th' item from the list. 2. Repeat 1 TASK: Calculate the n-th number from the 'lucky number list' ( 1 <= n <= 3000) My current code (it calculates the 3000 first lucky numbers in about a second on my machine - but unfortunately too slow): """ SPOJ Problem Set (classical) 1798. Assistance Required URL: http://www.spoj.pl/problems/ASSIST/ """ sieve = range(3, 33900, 2) luckynumbers = [2] while True: wanted_n = input() if wanted_n == 0: break while len(luckynumbers) < wanted_n: item = sieve[0] luckynumbers.append(item) items_to_delete = set(sieve[::item]) sieve = filter(lambda x: x not in items_to_delete, sieve) print luckynumbers[wanted_n-1]

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• Remove duplicates from a list of nested dictionaries

  - by user2924306

  I'm writing my first python program to manage users in Atlassian On Demand using their RESTful API. I call the users/search?username= API to retrieve lists of users, which returns JSON. The results is a list of complex dictionary types that look something like this: [ { "self": "http://www.example.com/jira/rest/api/2/user?username=fred", "name": "fred", "avatarUrls": { "24x24": "http://www.example.com/jira/secure/useravatar?size=small&ownerId=fred", "16x16": "http://www.example.com/jira/secure/useravatar?size=xsmall&ownerId=fred", "32x32": "http://www.example.com/jira/secure/useravatar?size=medium&ownerId=fred", "48x48": "http://www.example.com/jira/secure/useravatar?size=large&ownerId=fred" }, "displayName": "Fred F. User", "active": false }, { "self": "http://www.example.com/jira/rest/api/2/user?username=andrew", "name": "andrew", "avatarUrls": { "24x24": "http://www.example.com/jira/secure/useravatar?size=small&ownerId=andrew", "16x16": "http://www.example.com/jira/secure/useravatar?size=xsmall&ownerId=andrew", "32x32": "http://www.example.com/jira/secure/useravatar?size=medium&ownerId=andrew", "48x48": "http://www.example.com/jira/secure/useravatar?size=large&ownerId=andrew" }, "displayName": "Andrew Anderson", "active": false } ] I'm calling this multiple times and thus getting duplicate people in my results. I have been searching and reading but cannot figure out how to deduplicate this list. I figured out how to sort this list using a lambda function. I realize I could sort the list, then iterate and delete duplicates. I'm thinking there must be a more elegant solution. Thank you!

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• Math operations in nHibernate Criteria Query

  - by Richard Tasker

  Dear All, I am having troubles with a nHibernate query. I have a db which stores vehicle info, and the user is able to search the db by make, model, type and production dates. Make, model & type search is fine, works a treat, it is the productions dates I am having issues with. So here goes... The dates are stored as ints (StartMonth, StartYear, FinishMonth, FinishYear), when the end-user selects a date it is passed to the query as an int eg 2010006 (2010 * 100 + 6). below is part of the query I am using, FYI I am using Lambda Extensions. if (_searchCriteria.ProductionStart > 0) { query.Add<Engine>(e => ((e.StartYear * 100) + e.StartMonth) >= _searchCriteria.ProductionStart); } if (_searchCriteria.ProductionEnd > 0) { query.Add<Engine>(e => ((e.FinishYear * 100) + e.FinishMonth) <= _searchCriteria.ProductionEnd); } But when the query runs I get the following message, Could not determine member from ((e.StartYear * 100) + e.StartMonth) Any help would be great, Regards Rich

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• Simulate Windows Service with ASP.NET

  - by Bayonian

  Hi, I have small web app that generate PDF files as a report. I'm trying to delete those generated PDF files after 10 sec that they are generated. What I want to do is to read a folder with PDF files every 10 sec, and delete all the PDF files inside that folder. I read this post of Easy Background Tasks in ASP.NET. The following code is the VB version. Protected Sub Application_Start(ByVal sender As Object, ByVal e As EventArgs) AddTask("DoStuff", 10) End Sub Private Sub AddTask(ByVal name As String, ByVal seconds As Integer) OnCacheRemove = New CacheItemRemovedCallback(CacheItemRemoved) HttpRuntime.Cache.Insert(name, seconds, Nothing, DateTime.Now.AddSeconds(seconds), Cache.NoSlidingExpiration, CacheItemPriority.NotRemovable, _ OnCacheRemove) End Sub Public Sub CacheItemRemoved(ByVal k As String, ByVal v As Object, ByVal r As CacheItemRemovedReason) ' do stuff here if it matches our taskname, like WebRequest DeletePDFilesInFoler() ' re-add our task so it recurs AddTask(k, Convert.ToInt32(v)) End Sub But I got this error Delegate 'System.Web.Caching.CacheItemRemovedCallback' requires an 'AddressOf' expression or lambda expression as the only argument to its constructor. If this code works, where I should put it. Right, now I'm putting it in the master page. How to get this error out? Thank you

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• Mercurial Editor: "abort: The system cannot find the file specified"

  - by Killroy

  I have a problem getting Mercurial to recognise my editor. I have a file, c:\windows\notepad.exe and typing "notepad" at the command prompt works. I can commit by using the "-m" argument to supply the commit title. But a simple "hg commit" brings up the error. A call to "hg --traceback commit" brings up: Traceback (most recent call last): File "mercurial\dispatch.pyc", line 47, in _runcatch File "mercurial\dispatch.pyc", line 466, in _dispatch File "mercurial\dispatch.pyc", line 336, in runcommand File "mercurial\dispatch.pyc", line 517, in _runcommand File "mercurial\dispatch.pyc", line 471, in checkargs File "mercurial\dispatch.pyc", line 465, in <lambda> File "mercurial\util.pyc", line 401, in check File "mercurial\commands.pyc", line 708, in commit File "mercurial\cmdutil.pyc", line 1150, in commit File "mercurial\commands.pyc", line 706, in commitfunc File "mercurial\localrepo.pyc", line 836, in commit File "mercurial\cmdutil.pyc", line 1155, in commiteditor File "mercurial\cmdutil.pyc", line 1184, in commitforceeditor File "mercurial\ui.pyc", line 361, in edit File "mercurial\util.pyc", line 383, in system File "subprocess.pyc", line 470, in call File "subprocess.pyc", line 621, in __init__ File "subprocess.pyc", line 830, in _execute_child WindowsError: [Error 2] The system cannot find the file specified abort: The system cannot find the file specified I've tried setting the HGEDITOR environment variable, setting "visual =" and "editor =" in the Mercurial.ini file. I tried full path as well as command only. I also tried copying the notepad.exe file into both the current folder as well as the mercurial folder. Ideally I would like to use the editor at this location "C:\PortableApps\Notepad++Portable\Notepad++Portable.exe", but at this stage I would be happy with any editor!

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• How can I modify/merge Jinja2 dictionaries?

  - by Brian M. Hunt

  I have a Jinja2 dictionary and I want a single expression that modifies it - either by changing its content, or merging with another dictionary. >>> import jinja2 >>> e = jinja2.Environment() Modify a dict: Fails. >>> e.from_string("{{ x[4]=5 }}").render({'x':{1:2,2:3}}) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "jinja2/environment.py", line 743, in from_string return cls.from_code(self, self.compile(source), globals, None) File "jinja2/environment.py", line 469, in compile self.handle_exception(exc_info, source_hint=source) File "<unknown>", line 1, in template jinja2.exceptions.TemplateSyntaxError: expected token 'end of print statement', got '=' Two-stage update: Prints superfluous "None". >>> e.from_string("{{ x.update({4:5}) }} {{ x }}").render({'x':{1:2,2:3}}) u'None {1: 2, 2: 3, 4: 5}' >>> e.from_string("{{ dict(x.items()+ {3:4}.items()) }}").render({'x':{1:2,2:3}}) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "jinja2/environment.py", line 868, in render return self.environment.handle_exception(exc_info, True) File "<template>", line 1, in top-level template code TypeError: <lambda>() takes exactly 0 arguments (1 given) Use dict(x,**y): Fails. >>> e.from_string("{{ dict((3,4), **x) }}").render({'x':{1:2,2:3}}) Traceback (most recent call last): File "<stdin>", line 1, in <module> File "jinja2/environment.py", line 868, in render return self.environment.handle_exception(exc_info, True) File "<template>", line 1, in top-level template code TypeError: call() keywords must be strings So how does one modify the dictionary x in Jinja2 by changing an attribute or merging with another dictionary? This question is similar to: How can I merge two Python dictionaries as a single expression? -- insofar as Jinja2 and Python are analogous.

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• .net MVC RenderPartial renders information that is not in the model

  - by Andreas

  Hi, I have a usercontrol that is rendering a list of items. Each row contains a unique id in a hidden field, a text and a delete button. When clicking on the delete button I use jquery ajax to call the controller method DeleteCA (seen below). DeleteCA returns a new list of items that replaces the old list. [HttpPost] public PartialViewResult DeleteCA(CAsViewModel CAs, Guid CAIdToDelete) { int indexToRemove = CAs.CAList.IndexOf(CAs.CAList.Single(m => m.Id == CAIdToDelete)); CAs.CAList.RemoveAt(indexToRemove); return PartialView("EditorTemplates/CAs", CAs); } I have checked that DeleteCA is really removing the correct item. The modified list of CAs passed to PartialView no longer contains the deleted item. Something weird happens when the partial view is rendered. The number of items in the list is reduced but it is always the last element that is removed from the list. The rendered items does not correspond to the items in the list/model sent to PartialView. In the usercontrol file (ascx) I'm using both Model.CAList and lambda expression m = m.CAList. How is it possible for the usercontrol to render stuff that is not in the model sent to PartialView? Thanx Andreas

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• Looking for examples of "real" uses of continuations

  - by Sébastien RoccaSerra

  I'm trying to grasp the concept of continuations and I found several small teaching examples like this one from the Wikipedia article: (define the-continuation #f) (define (test) (let ((i 0)) ; call/cc calls its first function argument, passing ; a continuation variable representing this point in ; the program as the argument to that function. ; ; In this case, the function argument assigns that ; continuation to the variable the-continuation. ; (call/cc (lambda (k) (set! the-continuation k))) ; ; The next time the-continuation is called, we start here. (set! i (+ i 1)) i)) I understand what this little function does, but I can't see any obvious application of it. While I don't expect to use continuations all over my code anytime soon, I wish I knew a few cases where they can be appropriate. So I'm looking for more explicitely usefull code samples of what continuations can offer me as a programmer. Cheers!

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• Yahoo BOSS Python Library, ExpatError

  - by Wraith

  I tried to install the Yahoo BOSS mashup framework, but am having trouble running the examples provided. Examples 1, 2, 5, and 6 work, but 3 & 4 give Expat errors. Here is the output from ex3.py: gpython examples/ex3.py examples/ex3.py:33: Warning: 'as' will become a reserved keyword in Python 2.6 Traceback (most recent call last): File "examples/ex3.py", line 27, in <module> digg = db.select(name="dg", udf=titlef, url="http://digg.com/rss_search?search=google+android&area=dig&type=both&section=news") File "/usr/lib/python2.5/site-packages/yos/yql/db.py", line 214, in select tb = create(name, data=data, url=url, keep_standards_prefix=keep_standards_prefix) File "/usr/lib/python2.5/site-packages/yos/yql/db.py", line 201, in create return WebTable(name, d=rest.load(url), keep_standards_prefix=keep_standards_prefix) File "/usr/lib/python2.5/site-packages/yos/crawl/rest.py", line 38, in load return xml2dict.fromstring(dl) File "/usr/lib/python2.5/site-packages/yos/crawl/xml2dict.py", line 41, in fromstring t = ET.fromstring(s) File "/usr/lib/python2.5/xml/etree/ElementTree.py", line 963, in XML parser.feed(text) File "/usr/lib/python2.5/xml/etree/ElementTree.py", line 1245, in feed self._parser.Parse(data, 0) xml.parsers.expat.ExpatError: syntax error: line 1, column 0 It looks like both examples are failing when trying to query Digg.com. Here is the query that is constructed in ex3.py's code: diggf = lambda r: {"title": r["title"]["value"], "diggs": int(r["diggCount"]["value"])} digg = db.select(name="dg", udf=diggf, url="http://digg.com/rss_search?search=google+android&area=dig&type=both&section=news") Any help is appreciated. Thanks!

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• F# Active Pattern List.filter or equivalent

  - by akaphenom

  I have a records of types type tradeLeg = { id : int ; tradeId : int ; legActivity : LegActivityType ; actedOn : DateTime ; estimates : legComponents ; entryType : ShareOrDollarBased ; confirmedPrice: DollarsPerShare option; actuals : legComponents option ; type trade = { id : int ; securityId : int ; ricCode : string ; tradeActivity : TradeType ; enteredOn : DateTime ; closedOn : DateTime ; tradeLegs : tradeLeg list ; } Obviously the tradeLegs are a type off of a trade. A leg may be settled or unsettled (or unsettled but price confirmed) - thus I have defined the active pattern: let (|LegIsSettled|LegIsConfirmed|LegIsUnsettled|) (l: tradeLeg) = if Helper.exists l.actuals then LegIsSettled elif Helper.exists l.confirmedPrice then LegIsConfirmed else LegIsUnsettled and then to determine if a trade is settled (based on all legs matching LegIsSettled pattern: let (|TradeIsSettled|TradeIsUnsettled|) (t: trade) = if List.exists ( fun l -> match l with | LegIsSettled -> false | _ -> true) t.tradeLegs then TradeIsSettled else TradeIsUnsettled I can see some advantages of this use of active patterns, however i would think there is a more efficient way to see if any item of a list either matches (or doesn't) an actie pattern without having to write a lambda expression specifically for it, and using List.exist. Question is two fold: is there a more concise way to express this? is there a way to abstract the functionality / expression (fun l - match l with | LegIsSettled - false | _ - true) Such that let itemMatchesPattern pattern item = match item with | pattern -> true | _ -> false such I could write (as I am reusing this design-pattern): let curriedItemMatchesPattern = itemMatchesPattern LegIsSettled if List.exists curriedItemMatchesPattern t.tradeLegs then TradeIsSettled else TradeIsUnsettled Thoughts?

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• Trace PRISM / CAL events (best practice?)

  - by Christian

  Ok, this question is for people with either a deep knowledge of PRISM or some magic skills I just lack (yet). The Background is simple: Prism allows the declaration of events to which the user can subscribe or publish. In code this looks like this: _eventAggregator.GetEvent<LayoutChangedEvent>().Subscribe(UpdateUi, true); _eventAggregator.GetEvent<LayoutChangedEvent>().Publish("Some argument"); Now this is nice, especially because these events are strongly typed, and the declaration is a piece of cake: public class LayoutChangedEvent : CompositePresentationEvent<string> { } But now comes the hard part: I want to trace events in some way. I had the idea to subscribe using a lambda expression calling a simple log message. Worked perfectly in WPF, but in Silverlight there is some method access error (took me some time to figure out the reason).. If you want to see for yourself, try this in Silverlight: eA.GetEvent<VideoStartedEvent>().Subscribe(obj => TraceEvent(obj, "vSe", log)); If this would be possible, I would be happy, because I could easily trace all events using a single line to subscribe. But it does not... The alternative approach is writing a different functions for each event, and assign this function to the events. Why different functions? Well, I need to know WHICH event was published. If I use the same function for two different events I only get the payload as argument. I have now way to figure out which event caused the tracing message. I tried: using Reflection to get the causing event (not working) using a constructor in the event to enable each event to trace itself (not allowed) Any other ideas? Chris PS: Writing this text took me most likely longer than writing 20 functions for my 20 events, but I refuse to give up :-) I just had the idea to use postsharp, that would most likely work (although I am not sure, perhaps I end up having only information about the base class).. Tricky and so unimportant topic...

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