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• (How) Can I approximate a "dynamic" index (key extractor) for Boost MultiIndex?

  - by Sarah

  I have a MultiIndex container of boost::shared_ptrs to members of class Host. These members contain private arrays bool infections[NUM_SEROTYPES] revealing Hosts' infection statuses with respect to each of 1,...,NUM_SEROTYPES serotypes. I want to be able to determine at any time in the simulation the number of people infected with a given serotype, but I'm not sure how: Ideally, Boost MultiIndex would allow me to sort, for example, by Host::isInfected( int s ), where s is the serotype of interest. From what I understand, MultiIndex key extractors aren't allowed to take arguments. An alternative would be to define an index for each serotype, but I don't see how to write the MultiIndex container typedef ... in such an extensible way. I will be changing the number of serotypes between simulations. (Do experienced programmers think this should be possible? I'll attempt it if so.) There are 2^(NUM_SEROTYPES) possible infection statuses. For small numbers of serotypes, I could use a single index based on this number (or a binary string) and come up with some mapping from this key to actual infection status. Counting is still darn slow. I could maintain a separate structure counting the total numbers of infecteds with each serotype. The synchrony is a bit of a pain, but the memory is fine. I would prefer a slicker option, since I would like to do further sorts on other host attributes (e.g., after counting the number infected with serotype s, count the number of those infected who are also in a particular household and have a particular age). Thanks in advance.

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• SQL return ORDER BY result as an array

  - by EarthMind

  Is it possible to return groups as an associative array? I'd like to know if a pure SQL solution is possible. Note that I release that I could be making things more complex unnecessarily but this is mainly to give me an idea of the power of SQL. My problem: I have a list of words in the database that should be sorted alphabetically and grouped into separate groups according to the first letter of the word. For example: ape broom coconut banana apple should be returned as array( 'a' => 'ape', 'apple', 'b' => 'banana', 'broom', 'c' => 'coconut' ) so I can easily created sorted lists by first letter (i.e. clicking "A" only shows words starting with a, "B" with b, etc. This should make it easier for me to load everything in one query and make the sorted list JavaScript based, i.e. without having to reload the page (or use AJAX). Side notes: I'm using PostgreSQL but a solution for MySQL would be fine too so I can try to port it to PostgreSQL. Scripting language is PHP.

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• Modifying resource contents of a running executable

  - by mrwoik

  All, I store my application settings in a resource. When my program first loads, I read the specified resource using WinAPI. I then parse the retrieved byte data. This works flawlessly for me. Now let's say that a user alters a setting in my application. He/she checks a checkbox control. I would like to save the updated setting to my resource. However, it seems that my call to UpdateResource will not work while my application is running. I can't modify my resource data even though it is the same size. First, is it possible to modify a running image's resource data? Second, if that is not possible, what alternatives do I have for storing settings internally within my application? NOTE: I must have the settings within my running executable. They cannot be on the harddrive or in the registry. Please don't even suggest that as an option.

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• Porting Python algorithm to C++ - different solution

  - by cb0

  Hello, I have written a little brute string generation script in python to generate all possible combinations of an alphabet within a given length. It works quite nice, but for the reason I wan't it to be faster I try to port it to C++. The problem is that my C++ Code is creating far too much combination for one word. Heres my example in python: ./test.py gives me aaa aab aac aad aa aba .... while ./test (the c++ programm gives me) aaa aaa aaa aaa aa Here I also get all possible combinations, but I get them twice ore more often. Here is the Code for both programms: #!/usr/bin/env python import sys #Brute String Generator #Start it with ./brutestringer.py 4 6 "abcdefghijklmnopqrstuvwxyz1234567890" "" #will produce all strings with length 4 to 6 and chars from a to z and numbers 0 to 9 def rec(w, p, baseString): for c in "abcd": if (p<w - 1): rec(w, p + 1, baseString + "%c" % c) print baseString for b in range(3,4): rec(b, 0, "") And here the C++ Code #include <iostream> using namespace std; string chars="abcd"; void rec(int w,int b,string p){ unsigned int i; for(i=0;i<chars.size();i++){ if(b < (w-1)){ rec(w, (b+1), p+chars[i]); } cout << p << "\n"; } } int main () { int a=3, b=0; rec (a+1,b, ""); return 0; } Does anybody see my fault ? I don't have much experience with C++. Thanks indeed

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• Can Delphi 5 generate a .PDB file that VS can use?

  - by Vilx-

  We've got this large application written in Delphi 5, and development is ongoing to this day. There is research going on into migrating to newer versions, but so far there is no success, as some 3rd party components have not been updated in ages and do not work on later versions. In the meantime however people need to continue work on it. Now Delphi 5 IDE is no real treat. It's pretty bug-ridden and lacks a lot of features of contemporary IDEs which makes it difficult to use. Especially when it comes to debugging. So I was wondering - would it be possible to use Visual Studio in the process? As far as I know the .PDB file format is pretty old and is well documented. Could it be possible to make the Delphi compiler to somehow generate a .PDB files for it's compiled results? Then the program could be debugged with Visual Studio, possibly to a much greater extent than in the original IDE. Well, the absolute Holy Grail would be to move all development to VS, just keeping the compiler from Delphi, but I imagine that would be pretty impossible.

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• multiple form submission with one submit

  - by skylab

  I've been trying to think this through and figure out if it is possible or not. I'm using zen-cart as shopping cart software, but what I'd like to do, is hard code a page that is basically a list of 7-9 products, next to each product is a checkbox, so I'd like to figure out a way, via html,javascript or jquery to submit whichever forms(products) are checked to the cart. The typical form submission for a product looks something like this(sometimes there may be one or two additional hidden fields): <form name="cart_quantity" action="index.php?action=add_product" method="post" enctype="multipart/form-data"> <input type="hidden" name="cart_quantity" value="1"> <input type="hidden" name="products_id" value="7"> <input type="hidden" name="id[6]" value="9" id="attrib-6-9"> <input type="image" src="buy_button.png" alt="Add to Cart" title="Instructional Video Part 1: Add to Cart"> </form> There would be 7-9 of these on the page, each with a checkbox, so I'm assuming a script would need to figure out which ones where checked and submit them via the form action? Maybe there is a better way of going about this that I'm not thinking of because a)it's over my head or b)just haven't figured it out yet. Anyway is something like this possible?

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• C#: Determine Type for (De-)Serialization

  - by dbemerlin

  Hi, i have a little problem implementing some serialization/deserialization logic. I have several classes that each take a different type of Request object, all implementing a common interface and inheriting from a default implementation: This is how i think it should be: Requests interface IRequest { public String Action {get;set;} } class DefaultRequest : IRequest { public String Action {get;set;} } class LoginRequest : DefaultRequest { public String User {get;set;} public String Pass {get;set;} } Handlers interface IHandler<T> { public Type GetRequestType(); public IResponse HandleRequest(IModel model, T request); } class DefaultHandler<T> : IHandler<T> // Used as fallback if the handler cannot be determined { public Type GetRequestType() { return /* ....... how to get the Type of T? ((new T()).GetType()) ? .......... */ } public IResponse HandleRequest(IModel model, T request) { /* ... */ } } class LoginHandler : DefaultHandler<LoginRequest> { public IResponse HandleRequest(IModel mode, LoginRequest request) { } } Calling class Controller { public ProcessRequest(String action, String serializedRequest) { IHandler handler = GetHandlerForAction(action); IRequest request = serializer.Deserialize<handler.GetRequestType()>(serializedRequest); handler(this.Model, request); } } Is what i think of even possible? My current Solution is that each handler gets the serialized String and is itself responsible for deserialization. This is not a good solution as it contains duplicate code, the beginning of each HandleRequest method looks the same (FooRequest request = Deserialize(serializedRequest); + try/catch and other Error Handling on failed deserialization). Embedding type information into the serialized Data is not possible and not intended. Thanks for any Hints.

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• C++ - Distributing different headers than development

  - by Ben

  I was curious about doing this in C++: Lets say I have a small library that I distribute to my users. I give my clients both the binary and the associated header files that they need. For example, lets assume the following header is used in development: #include <string> ClassA { public: bool setString(const std::string & str); private: std::string str; }; Now for my question. For deployment, is there anything fundamentally wrong with me giving a 'reduced' header to my clients? For example, could I strip off the private section and simply give them this: #include <string> ClassA { public: bool setString(const std::string & str); }; My gut instinct says "yes, this is possible, but there are gotchas", so that is why I am asking this question here. If this is possible and also safe, it looks like a great way to hide private variables, and thus even avoid forward declaration in some cases. I am aware that the symbols will still be there in the binary itself, and that this is just a visibility thing at the source code level. Thanks!

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• HeadJS ready for both document and script

  - by Yashua

  Current code: head.ready(function() { console.log($('.thing a').val()); }); It will sometimes fail with error that $ is not ready. I have loaded jquuery earlier with the label 'jquery'. Neither of these work: head.ready(document, function() { console.log($('.thing a').val()); }); head.ready('jquery', function() { console.log($('.thing a').val()); }); I would like to not do this if possible: head.ready(document, function() { head.ready('jquery', function() { console.log($('.thing a').val()); }); }); And also avoid refactoring current code to place that snippet at bottom of body though that I think may be the solution. Is it possible with HeadJS to define a ready call() using head.ready(), that is not placed at the bottom, that will wait for both a labeled script and the DOM to be loaded? UPDATE: the nested script doesn't actually work. I think the inner one erases/superseds the other :(

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• C++ Conceptual problem with (Pointer) Pointers

  - by Ptr

  I have a structure usually containing a pointer to an int. However, in some special cases, it is necessary that this int pointer points to another pointer which then points to an int. Wow: I mentioned the word pointer 5 times so far! Is this even possible? I thought about it that way: Instead of using a second int pointer, which is most likely not possible as my main int pointer can only point to an int and not to another int pointer, I could make it a reference like this: int intA = 1; int intB = 2; int& intC = intB; int* myPointers[ 123 ]; myPointers[ 0 ] = &intA; myPointers[ 1 ] = &intB; myPointers[ 3 ] = &intC; So the above would do what I want: The reference to intB (intC) behaves quite like I want it to (If it gets changed it also changes intB) The problem: I can't change references once they are set, right? Or is there a way? Everything in short: How do I get a value to work with * (pointers) and ** (pointers to pointers)?

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• Custom progress bar label text via binding

  - by Alexander K

  I was playing with progress bar customization in Silverlight application. What I want to reach is to have progress bar label to show current its state in the following format: "Value / Maximum". So, user will see what is the current value, and what is the maximum possible value. Here is a style for progress bar I use: <Style x:Key="ProgressBarStyle" TargetType="ProgressBar"> <Setter Property="Width" Value="97.21" /> <Setter Property="Height" Value="19" /> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="ProgressBar"> <Canvas x:Name="LevelField" Width="99" Height="21"> ... <TextBlock ... DataContext="{TemplateBinding Value}" Text="{Binding Converter={StaticResource DecNumberToStringConverter}}"/> </Canvas> </ControlTemplate> </Setter.Value> </Setter> </Style> The way I want to implement this, is to have a value converter, that will convert current value and maximum possible into the proper string. It does work properly, if it is written like above. However, I also need to provide ConverterParameter for Convertor, but not sure how to make it. When I write like this: , ConvertParameter={Binding Maximum}, it shows error on start, that Text attribute is not found in TextBlock. I was also trying to set DataContext as {RelativeSource Self}, but then it didn't displays error that DataContext attribute is not found. How to make the described progress bar label properly?

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• How to: StructureMap and configuration based on runtime parameters?

  - by user981375

  In a nutshell - I want to be able to instantiate object based on runtime parameters. In this particular case there are only two parameters but the problem is that I'm facing different permutations of these parameters and it gets messy. Here is the situation: I want to get an instance of an object specific to, say, given country and then, say, specific state/province. So, considering the US, there are 50 possible combinations. In reality it's less than that but that's the max. Think of it this way, I want to find out what's the penalty for smoking pot in a given country/state, I pass this information in and I get instantiated object telling me what it is. To the code (for reference only): interface IState { string Penalty { get; } } interface ICountry { IState State { get; set; } string Name { get; } } class BasePenalty : IState { virtual public string Penalty { get { return "Slap on a wrist"; } } } class USA : ICountry { public USA(IState state) { State = state; } public IState State { get; set; } public string Name { get { return "USA"; } } } class Florida: BasePenalty { public override string Penalty { get { return "Public beheading"; } } } // and so on ... I defined other states // which have penalties other than the "Slap on a wrist" How do I configure my container that when given country and state combination it will return the penalty? I tried combinations of profile and contextual binding but that configuration was directly proportional to the number of classes I've created. I have already gone thru trouble of defining different combinations. I'd like to avoid having to do the same during container configuration. I want to inject State into the Country. Also, I'd like to return UsaBasePenalty value in case state is not specified. Is that possible? Perhaps these is something wrong with the design.

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• Django: Storing ordered, arbitrary references

  - by Sarah

  I'm new to Django, and I'm not sure what I want is possible: I have a number of items that I want each AppUser (extended User model) to be able to reference. That is, given an AppUser, I want to be able to extract its list of items in the way that AppUser has chosen to order them. In general, these items would actually be references to something else in the database, and this led me to one possible solution: Store the keys for the given objects in a CommaSeparatedIntegerField in AppUser. This way, a user could have stored {7, 3, 232, 42, 1} in their items field and both the references and their preferred order would be stored. However, this feels hacky. Since most db backends store CommaSeparatedIntegerField as a VARCHAR internally, the user is not only limited by a number of objects, but also the number of digits in their chosen items. Eg. "you may store 10 items if you choose items with itemID < 10, but only 5 items if 10 < itemID < 100". Is there a better way to do this?

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• How to clean up my code

  - by simion

  Being new to this i realy am trying to learn how to keep code as simple as possible, whilst doing the job its supposed to. The question i have done is from project eulur, it says Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be: 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ... Find the sum of all the even-valued terms in the sequence which do not exceed four million. Here is my code below, i was wondering what the best way of simplifying this would be, for a start removing all of the .get(list.length()-1 )..... stuff would be a good start if possible but i dont really no how to? Thanks public long fibb() { ArrayList<Integer> list = new ArrayList<Integer>(); list.add(1); list.add(2); while((list.get(list.size() - 1) + (list.get(list.size() - 2)) < 4000000)){ list.add((list.get(list.size()-1)) + (list.get(list.size() - 2))); } long value = 0; for(int i = 0; i < list.size(); i++){ if(list.get(i) % 2 == 0){ value += list.get(i); } } return value; }

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• formmail to email in database

  - by aarontb

  Here's what I need to setup...and I am not well versed in PHP/SQL...but this is what I'm trying to do. On the New User database, I will have a section where they can have information sent to their phone using the provider's default e-mail to text msg (i.e. [email protected].) New User: Input number: ______________(2225551212 format, no hyphens, etc.) Select Provider: (Drop-down menu with proper @provider.ext...) Then the formmail, when sent, if for specific user will get ($phone".@."$provider); or something like that and send a preset message like: $user."requested information on ".$product."on".$date." at ".$time."."; Is this possible? The $user, $product, $date, $time all are generated directly from the most recent input page for a database. Is this possible? Please help!

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• How do I vertcally align thumbnails of unknown height using jQuery?

  - by playahabana

  Ok, I am a complete beginner to this, in fact I am still building my first website. I am attempting to do this all by hand-coding without a CMS in order to try and learn as much possible as quickly as possible. If this post is in the wrong place I apologise, and a pointer to right place would be appreciated. Here goes, I am trying to peice together a bit of jQuery that will automatically vertically align my thumbnails in my image gallery (they are all different sizes). They are within fixed size div's and the function I am attempting looks something like this: <script type="text/javascript"> $('#ul.photo).bind(function() { var smartVert=$(this); var phty=ob.("ul.photo img").height(); //get height of photos var phtdif=Math.floor(208 - phty); //subtract height of photo from div height var phttop=Math.floor(phtdif / 2); //gets padding reqd. $ob.("ul.photo").css({'padding-top' : phttop}) //sets padding to center thumbnail }); smartVert(); unsurprisingly this doesn't work, if some kindly soul could take pity on a total noob, and point out where I am going wrong (probably in writing complete gibberish would be my first guess) it would be greatly appreciated- even if you could just point me in the direcion of a tutorial regarding these things, I have looked and found one reference that said such a function was easy to create, but it did not elaborate. thankyou in advance

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• Events + Adapter Pattern

  - by Stretto

  I have an adapter pattern on a generic class that essentially adapts between types: class A<T> { event EventHandler e; } class Aadapter<T1, T2> : A<T1> { A<T2> a; Aadapter(A<T2> _a) { a = _a; } } The problem is that A contains an event. I effectively want all event handlers assigned to Adapter to fall through to a. It would be awesome if I could assign the a's event handler to adapter's event handler but this is impossible? The idea here is that A is almost really just A but we need a way to adapt the them. Because of the way event's work I can't how to efficiently do it except manually add two event handlers and when they are called they "relay" the to the other event. This isn't pretty though and it would seem much nicer if I could have something like class A<T> { event EventHandler e; } class Aadapter<T1, T2> : A<T1> { event *e; A<T2> a; Aadapter(A<T2> _a) { a = _a; e = a.e; } } in a sense we have a pointer to the event that we can assign a2's event to. I doubt there is any simple way but maybe someone has some idea to make it work. (BTW, I realize this is possible with virtual events but I'd like to avoid this if at all possible)

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• custom sorting or ordering a table without resorting the whole shebang

  - by fuugus

  for ten years we've been using the same custom sorting on our tables, i'm wondering if there is another solution which involves fewer updates, especially since today we'd like to have a replication/publication date and would'nt like to have our replication replicate unnecessary entries. i had a look into nested sets, but it does'nt seem to do the job for us. base table: id | a_sort ---+------- 1 10 2 20 3 30 after inserting insert into table (a_sort) values(15) an entry at the second position. id | a_sort ---+------- 1 10 2 20 3 30 4 15 ordering the table with select * from table order by a_sort and resorting all the a_sort entries, updating at least id=(2,3,4) will of course produce the desired output id | a_sort ---+------- 1 10 4 20 2 30 3 40 the column names, the column count, datatypes, a possible join, possible triggers or the way the resorting is done is/are irrelevant to the problem. also we've found some pretty neat ways to do this task fast. only; how the heck can we reduce the updates in the db to 1 or 2 max. seems like an awfully common problem. the captain obvious in me thougth once "use an a_sort float(53), insert using a fixed value of ordervaluefirstentry+abs(ordervaluefirstentry-ordervaluenextentry)/2".. but this would only allow around 1040 "in between" entries - so never resorting seems a bit problematic ;)

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• Creating multiple instances of a generic database

  - by sagekilla

  Hi all, currently I'm trying to have a setup where a generic database is distributed to students. They would develop an application using this database (Say a shopping cart application), submit their project onto our server, and then it would be graded automatically. These databases are being run in Microsoft SQL Server 2005. We're using user instances to instantiate each database, and multiple requests could be serviced at once. But, the problem is when more than one student submitted a project to be graded, the first database to be instantiated would be the only one and would overwrite all other copies that were currently open. So if stu1 modified his database and stu2 and stu3 had their projects being graded concurrently, at the end of the grading stu1, stu2, and stu3 would have identical DB's at the end. Is there any way I can have multiple independent copies of a generic database, each of which I can load concurrently and modify without having any changes made to any one affecting the others? I did a little reading, and thought it might be possible to do something along the lines of: Student submits project Attach the database with unique db name (specified by student) Do all necessary operations Detach the database I'm unsure if this would fix our problem or be possible, so any help would be much appreciated!

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• How to easily apply a function to a collection in C++

  - by Jesse Beder

  I'm storing images as arrays, templated based on the type of their elements, like Image<unsigned> or Image<float>, etc. Frequently, I need to perform operations on these images; for example, I might need to add two images, or square an image (elementwise), and so on. All of the operations are elementwise. I'd like get as close as possible to writing things like: float Add(float a, float b) { return a+b; } Image<float> result = Add(img1, img2); and even better, things like complex ComplexCombine(float a, float b) { return complex(a, b); } Image<complex> result = ComplexCombine(img1, img2); or struct FindMax { unsigned currentMax; FindMax(): currentMax(0) {} void operator(unsigned a) { if(a > currentMax) currentMax = a; } }; FindMax findMax; findMax(img); findMax.currentMax; // now contains the maximum value of 'img' Now, I obviously can't exactly do that; I've written something so that I can call: Image<float> result = Apply(img1, img2, Add); but I can't seem to figure out a generic way for it to detect the return type of the function/function object passed, so my ComplexCombine example above is out; also, I have to write a new one for each number of arguments I'd like to pass (which seems inevitable). Any thoughts on how to achieve this (with as little boilerplate code as possible)?

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• C++ and its type system: How to deal with data with multiple types?

  - by sub

  "Introduction" I'm relatively new to C++. I went through all the basic stuff and managed to build 2-3 simple interpreters for my programming languages. The first thing that gave and still gives me a headache: Implementing the type system of my language in C++ Think of that: Ruby, Python, PHP and Co. have a lot of built-in types which obviously are implemented in C. So what I first tried was to make it possible to give a value in my language three possible types: Int, String and Nil. I came up with this: enum ValueType { Int, String, Nil }; class Value { public: ValueType type; int intVal; string stringVal; }; Yeah, wow, I know. It was extremely slow to pass this class around as the string allocator had to be called all the time. Next time I've tried something similar to this: enum ValueType { Int, String, Nil }; extern string stringTable[255]; class Value { public: ValueType type; int index; }; I would store all strings in stringTable and write their position to index. If the type of Value was Int, I just stored the integer in index, it wouldn't make sense at all using an int index to access another int, or? Anyways, the above gave me a headache too. After some time, accessing the string from the table here, referencing it there and copying it over there grew over my head - I lost control. I had to put the interpreter draft down. Now: Okay, so C and C++ are statically typed. How do the main implementations of the languages mentioned above handle the different types in their programs (fixnums, bignums, nums, strings, arrays, resources,...)? What should I do to get maximum speed with many different available types? How do the solutions compare to my simplified versions above?

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• How do I access abstract private data from derived class without friend or 'getter' functions in C++?

  - by John

  So, I am caught up in a dilemma right now. How am I suppose to access a pure abstract base class private member variable from a derived class? I have heard from a friend that it is possible to access it through the base constructor, but he didn't explain. How is it possible? There are some inherited classes from base class. Is there any way to gain access to the private variables ? class Base_button { private: bool is_vis; Rect rButton; public: // Constructors Base_button(); Base_button( const Point &corner, double height, double width ); // Destructor virtual ~ Base_button(); // Accessors virtual void draw() const = 0; bool clicked( const Point &click ) const; bool is_visible() const; // Mutators virtual void show(); virtual void hide(); void move( const Point &loc ); }; class Button : public Base_button { private: Message mButton; public: // Constructors Button(); Button( const Point &corner, const string &label ); // Acessors virtual void draw() const; // Mutators virtual void show(); virtual void hide(); }; I want to be able access Rect and bool in the base class from the subclass

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• Why use shorter VARCHAR(n) fields?

  - by chryss

  It is frequently advised to choose database field sizes to be as narrow as possible. I am wondering to what degree this applies to SQL Server 2005 VARCHAR columns: Storing 10-letter English words in a VARCHAR(255) field will not take up more storage than in a VARCHAR(10) field. Are there other reasons to restrict the size of VARCHAR fields to stick as closely as possible to the size of the data? I'm thinking of Performance: Is there an advantage to using a smaller n when selecting, filtering and sorting on the data? Memory, including on the application side (C++)? Style/validation: How important do you consider restricting colunm size to force non-sensical data imports to fail (such as 200-character surnames)? Anything else? Background: I help data integrators with the design of data flows into a database-backed system. They have to use an API that restricts their choice of data types. For character data, only VARCHAR(n) with n <= 255 is available; CHAR, NCHAR, NVARCHAR and TEXT are not. We're trying to lay down some "good practices" rules, and the question has come up if there is a real detriment to using VARCHAR(255) even for data where real maximum sizes will never exceed 30 bytes or so. Typical data volumes for one table are 1-10 Mio records with up to 150 attributes. Query performance (SELECT, with frequently extensive WHERE clauses) and application-side retrieval performance are paramount.

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• Deserialization of a DataSet... deal with column name changes? how to migrate data from one column to another?

  - by Brian Kennedy

  So, we wanted to slightly generalize a couple columns in our typed dataset... basically dropped a foreign key constraint and then wanted to change a couple column names to better reflect their new state. All that is easy. The problem is that our users may have serialized out the old version of the DataSet as XML. We want to be able to read those old XML files and deserialize them into the revised DataSet. It seems that would be a fairly common desire... but I haven't yet figured out the right thing to search the internet for. One possible solution would seem to be some way to give a DataColumn an alias or alternate name such that when it reads the old column name, it knows that data can be read into the column with the new column name. I can find no support for any such thing. Another approach would seem to be an "after deserialization" method of some sort... so, I would let it read in the old column values into a normal DataColumn with that name, and then in the "after deserialization" method I would just move the data from the obsolete column into the new column, and then delete the old columns. That would seem to generalize to many other situations... and having such events or hooks is pretty common in ADO.NET. But I have looked for such a hook and haven't yet found it. If no "after deserialization" hook, it would seem I ought to be able to override ReadXml or ReadXmlSerializable methods to call the base and then do my "after" stuff to fix up old data into new. But it does not appear that is possible. Soooo, I have to think backward compatibility with old serialized DataSets and simple data migration would be a well-solved problem... so, trying to reinvent that wheel seems silly. But so far, I haven't seemed to find any documentation on doing those things. Suggestions? What is best practice for this?

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• How can I layout a sidebar or pullquote?

  - by Rich

  I have 4 divs in a fixed width layout: a, b, c, and d, and they are ordered in the html like this: <div id="a"> </div> <div id="b"> </div> <div id="c"> </div> <div id="d"> </div> Using CSS, I want them to be laid out with divs a, b, and d in a vertical column, and div c to the right of and top-aligned with div b, like this: aaa aaa aaa bbbccc bbbccc bbbccc ddd ddd ddd I need this layout to work even though the divs contain unknown content, and so could be of varying length: aaa aaa aaa bbbccc bbbccc dddccc dddccc ddd or: aaa aaa aaa bbbccc bbb bbb ddd ddd ddd or even (if possible): aaa aaa bbbccc dddccc eeeccc eee I can't simply float div c to the right and then move it up, because, without using Javascript, I don't know the height of div b, and so don't know how much to move it up by. Is this possible in HTML and CSS, without reordering the divs?

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