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  • In C# should I reuse a function / property parameter to compute cleaner temporary value or create a

    - by Hamish Grubijan
    The example below may not be problematic as is, but it should be enough to illustrate a point. Imagine that there is a lot more work than trimming going on. public string Thingy { set { // I guess we can throw a null reference exception here on null. value = value.Trim(); // Well, imagine that there is so much processing to do this.thingy = value; // That this.thingy = value.Trim() would not fit on one line ... So, if the assignment has to take two lines, then I either have to abusereuse the parameter, or create a temporary variable. I am not a big fan of temporary variables. On the other hand, I am not a fan of convoluted code. I did not include an example where a function is involved, but I am sure you can imagine it. One concern I have is if a function accepted a string and the parameter was "abused", and then someone changed the signature to ref in both places - this ought to mess things up, but ... who would knowingly make such a change if it already worked without a ref? Seems like it is their responsibility in this case. If I mess with the value of value, am I doing something non-trivial under the hood? If you think that both approaches are acceptable, then which do you prefer and why? Thanks.

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  • implementing user tracking (logging) in Rails 3

    - by seth.vargo
    Hi, I'm creating a Rails application in which logging individual user actions is vital. Every time a user clicks a url, I want to log the action along with all parameters. Here is my current implementation: class CreateActivityLogs < ActiveRecord::Migration create_table :activity_logs do |t| t.references :user t.string :ip_address t.string :referring_url t.string :current_url t.text :params t.text :action t.timestamps end end   class ActivityLog < ActiveRecord::Base belongs_to :user end In a controller, I'd like to be able to do something like the following: ... ActivityLog::log @user.id, params, 'did foo with bar' ... I'd like to have the ActivityLog::log method automatically get the IP address, referring url, and current url (I know how to do this already) and create a new record in the table. So, my questions are: How do I do this? How do I use ActivityLog without having to create an instance everytime I want to log? Is this the best way? Some people have argued for a flat-file log for this kind of logging - however, I want admins to be able to see a user's activity in the backend as well, so I thought a database solution may be better?

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  • Best way to implement some type of ITaggable interface

    - by Jack
    I've got a program I'm creating that reports on another certain programs backup xml files. I've gotten to the point where I need to implement some type of ITaggable interface - but am unsure how to go about it code wise. My idea is that each item (BackupClient, BackupVersion, and BackupFile) should implement an ITaggable interface for highlighting old, out of date, or non-existent files in their HTML or Excel report. The user will be able to specify tags in the settings. My question is this, how can a user dynamically specify a "tag" such as File Date 3 days old? - Background Color = Red. Actually I guess my question is more, how can I, the programmer, implement this dynamically? I was thinking Expression trees, but am unsure this is the way to go as I havn't studied them much. I know my ITaggable interface would have methods such as AddTag(T tag), RemoveTag(T tag), but what exactly specifies the criteria for the tag to be added? I realize this may be subjective, and can be marked as wiki if need be, but I truly am stuck. Any input would be greatly helpful!

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  • C++ - Where to throw exception?

    - by HardCoder1986
    Hello! I have some kind of an ideological question, so: Suppose I have some templated function template <typename Stream> void Foo(Stream& stream, Object& object) { ... } which does something with this object and the stream (for example, serializes that object to the stream or something like that). Let's say I also add some plain wrappers like (and let's say the number of these wrappers equals 2 or 3): void FooToFile(const std::string& filename, Object& object) { std::ifstream stream(filename.c_str()); Foo(stream, object); } So, my question is: Where in this case (ideologically) should I throw the exception if my stream is bad? Should I do this in each wrapper or just move that check to my Foo, so that it's body would look like if (!foo.good()) throw (something); // Perform ordinary actions I understand that this may be not the most important part of coding and these solutions are actually equal, but I just wan't to know "the proper" way to implement this. Thank you.

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  • Calculating with a variable outside of its bounds in C

    - by aquanar
    If I make a calculation with a variable where an intermediate part of the calculation goes higher then the bounds of that variable type, is there any hazard that some platforms may not like? This is an example of what I'm asking: int a, b; a=30000; b=(a*32000)/32767; I have compiled this, and it does give the correct answer of 29297 (well, within truncating error, anyway). But the part that worries me is that 30,000*32,000 = 960,000,000, which is a 30-bit number, and thus cannot be stored in a 16-bit int. The end result is well within the bounds of an int, but I was expecting that whatever working part of memory would have the same size allocated as the largest source variables did, so an overflow error would occur. This is just a small example to show my problem, I am trying to avoid using floating points by making the fraction be a fraction of the max amount able to be stored in that variable (in this case, a signed integer, so 32767 on the positive side), because the embedded system I'm using I believe does not have an FPU. So how do most processors handle calculations out of the bounds of the source and destination variables?

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  • Initializing an object to all zeroes

    - by dash-tom-bang
    Oftentimes data structures' valid initialization is to set all members to zero. Even when programming in C++, one may need to interface with an external API for which this is the case. Is there any practical difference between: some_struct s; memset(s, 0, sizeof(s)); and simply some_struct s = { 0 }; Do folks find themselves using both, with a method for choosing which is more appropriate for a given application? For myself, as mostly a C++ programmer who doesn't use memset much, I'm never certain of the function signature so I find the second example is just easier to use in addition to being less typing, more compact, and maybe even more obvious since it says "this object is initialized to zero" right in the declaration rather than waiting for the next line of code and seeing, "oh, this object is zero initialized." When creating classes and structs in C++ I tend to use initialization lists; I'm curious about folks thoughts on the two "C style" initializations above rather than a comparison against what is available in C++ since I suspect many of us interface with C libraries even if we code mostly in C++ ourselves.

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  • Need help managing MySql connections

    - by David Jenings
    I'm having trouble finding a clear explanation of connection pooling. I'm building an app using the .NET connector I downloaded from mysql.com. The app only needs one db connection but will be running simultaneously on about 6 machines on my network. Normally, I'd create the connection at startup and just leave it. But I'm seeing lots of posts from people who say that's bad practice. Also I'm concerned about timeouts. My app will run 24/7 and there may be extended periods without database activity. I'm leaning toward the following: using (MySqlConnection conn = new MySqlConnection(connStr)) { conn.Open(); // use connection } But I'm not sure I understand what's going on in the background. Is this actually closing the connection and allowing gc to kill the object, or is there a built in pooling behavior that preserves the object and redelivers it the next time I try to create one? I certainly don't want the app reauthenticating across the network every time I hit the database. Can anyone offer me some advise?

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  • How to store and synchronize a big list of strings

    - by Joel
    I have a large database table in SQLExpress on Windows, with a particular field of interest 'code'. I have an Apache web server with MySQL on Linux. The web application on the Linux box needs access to the list of all codes. The only thing it will use the list for is checking for the existence of a given code. Having the Linux server call out to the Windows server is impractical as the Windows server is behind a NAT'ed office internet connection, and it may not always be accessible. I have set it so the Windows server will push the list of codes to the web server by means of a simple HTTP POST request. However, at this point I have not implemented the storage of the codes on the Linux box. Should I store them in a MySQL table with a single field 'code'? Then I get fast indexed lookups O(1), however I think synchronization will be an issue - given an updated list of codes, pushed from the Windows box, how would I optimally synchronize the list with the database? TRUNCATE, followed by INSERT? Should I instead store them in a flat file? Then I have O(n) look up time rather than O(1). Additionally an extra constant-time overhead too, as I will be processing the file in Ruby. However, synchronization is easy - simply replace the file.

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  • [RAILS] Why is ssl_requirement clearing the Flash? (Chrome Mac)

    - by aaronrussell
    I am using ssl_requirement and since setting it up, my application's Flash messages are disappearing. I've modified the plugin slightly as accounts can optionally have a domain mapped to their account. In that case the non-ssl areas of the site should use the mapped domain, whereas the ssl areas should use the subdomain: def ensure_proper_protocol return true if ssl_allowed? if ssl_required? && !request.ssl? redirect_to "https://#{@account.subdomain}." + APP_CONF[:domain] + request.request_uri flash.keep return false elsif request.ssl? && !ssl_required? redirect_to "http://#{@account.sub_or_mapped_domain}" + request.request_uri flash.keep return false end end The application is broadly split into a website (front end) and an admin (back end). ALL of the admin area uses SSL so in the AdminController I have overwritten ssl_required? with: protected def ssl_required? return false if RAILS_ENV == "test" || RAILS_ENV == "development" true end Interestingly, Flash messages work fine in the development environment, where I am bypassing requiring SSL, but in my production environment where SSL is required, all Flash are gone. Any ideas? EDIT I've done some further testing and can add that this problem is ONLY occurring in Chrome on the Mac. Other Mac browsers and Chrome on windows are displaying the Flash messages as expected. This may be a bug with Chrome on the Mac then...?

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  • How can I use SCM on linked files in VS2008 projects?

    - by Tom Bushell
    Background: I'm using Visual-SVN V. 1.7.5 with VS2008. I'm fairly new to SVN. I have a Solution that uses source files that will be shared with other Solutions. I've put these files in a folder called "Shared", and added them to my Solution using "Add - Existing Item... - Add As Link" which works fine as far as VS2008 is concerned. But when I try to add the linked files to SVN using the "Add to Suversion" menu item on the file's context menu, I get a warning: "...not added to Subversion because it is out of working copy. Please setup working copy root using Visual SVN - Set Working Copy Root menu". I tried this, but this seems to change the root directory of the whole solution - not what I want to do. Googling and searching SO indicates that I may want to set up some SVN Externals. I tried to follow the examples, using the command line for the first time with Visual-SVN. But I just got a bunch of error messages I didn't understand. Questions: Are Externals the way to go here? If so, can someone provide some detailed, step-by-step help on how to do this with Visual-SVN?

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  • Modifying html of dom element that was created after page loaded

    - by Ben321
    I have two separate AJAX calls. One that gets a list of items from a txt file and creates an HTML table out of them and one that talks to a database to find how much each item costs and then lists this in the corresponding table cell for each item (I know this may sound like a strange approach, but it's a good option in our case...). The issue is that the price is not getting written to the table since the table is created (or to be precise, the rows of the table are created) after the page loads. I'm not sure how to fix this. $(document).ready(function() { makeItemTable(); listPrices(); ... }); function makeItemTable() { $.ajax({ url: 'products.php', type: 'GET' }) .done(function(response) { $('.price-table > tbody').html(response); }) } function listPrices() { .ajax({ url: 'prices.php', type: 'GET' }) .done(function(response) { priceData = $.parseJSON(response); $('.price-table tr').each(function() { var item = $(this).find('td:nth-child(1)').text(); if (priceData[item]) { var price = priceData[item]; $(this).find('td:nth-child(2)').text(price); } }) }

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  • Defining implicit and explicit casts for C# interfaces

    - by ehdv
    Is there a way to write interface-based code (i.e. using interfaces rather than classes as the types accepted and passed around) in C# without giving up the use of things like implicit casts? Here's some sample code - there's been a lot removed, but these are the relevant portions. public class Game { public class VariantInfo { public string Language { get; set; } public string Variant { get; set; } } } And in ScrDictionary.cs, we have... public class ScrDictionary: IScrDictionary { public string Language { get; set; } public string Variant { get; set; } public static implicit operator Game.VariantInfo(ScrDictionary s) { return new Game.VariantInfo{Language=sd.Language, Variant=sd.Variant}; } } And the interface... public interface IScrDictionary { string Language { get; set; } string Variant { get; set; } } I want to be able to use IScrDictionary instead of ScrDictionary, but still be able to implicitly convert a ScrDictionary to a Game.VariantInfo. Also, while there may be an easy way to make this work by giving IScrDictionary a property of type Game.VariantInfo my question is more generally: Is there a way to define casts or operator overloading on interfaces? (If not, what is the proper C# way to maintain this functionality without giving up interface-oriented design?)

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  • Syncing objects between two devices with different system times

    - by Mike Weller
    Hi there. I'm syncing objects between two devices. Objects have a lastModified property. If both devices have modified an object, then during the next sync the version of the object with the most recent lastModified is chosen on both devices. So we don't do fine-grained merging, only 'most recent version' merging. The problem is this. When one device receives a list of changed objects it can't reliably compare the lastModified of received objects to its own because the system times on the two devices may be different. I considered having each device send its current date/time during the sync. Then each calculates the difference between the remote time and the local time to compare the dates properly. But if there is lag between sending a date and the remote device receiving it, this causes incorrect comparisons with objects that were modified at the same time (or very close together in time). i.e. both devices think the remote object is newer and they end up with different objects. I hope I have explained this clearly enough. There must be a common solution to this kind of problem but my brain isn't coming up with anything. Any suggestions? Thanks in advance...

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  • Position footer to bottom of window or page, whichever is larger

    - by BenM
    I am currently working on a site that requires a footer to be placed either at the bottom of the window, or the bottom of the page content, whichever is lower. I have tried using the height: 100% method, but this causes a problem. I also have a position: fixed header, and some padding on my content (defined in pixels). Also, the height of the content may change after the page has loaded (use of accordions, etc.), so I wonder if there's a pure CSS way to position the footer to either the bottom of the window, or the bottom of the document, while still allowing pixel padding and so forth. Here's an outlined structure of the HTML: <header></header> <div class="content"> <footer></footer> </div> I have also put together a Fiddle to demonstrate how the CSS works at the moment: http://jsfiddle.net/LY6Zs/. I am unfortunately unable to change the HTML structure (i.e. breaking out the footer element from .content.

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  • Setting the mysql root user password on mac

    - by madaura
    I just Install MySQL on Mac OS X. The next step was setting the root user password, do I did the next: 1-Launch the terminal app to access the unix command line. 2-Under the unix prompt I executed the next commands: madaura$ cd /usr/local/mysql/bin madaura$ ./mysqladmin -u root password 'password' But, when I execute the command madaura$ ./mysql -u root, this is the answer: Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 224 Server version: 5.5.13 MySQL Community Server (GPL) Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. Oracle is a registered trademark of Oracle Corporation and/or its affiliates. Other names may be trademarks of their respective owners. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> I can get in to the mysql command line without password! Any ideas? Thanks a lot!

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  • [C#] How do I make hierarchy of objects from two alternating classes?

    - by Millicent
    Here's the scenario: I have two classes ("Page" and "Field"), that are descended from a common class ("Pield"). They represent tags in an XML file and are in the following hierarchy: <page> <field> <page> ... </page> ... </field> ... </page> I.e.: Page and Field objects are in a hierarchy of alternating type (there may be more than one Page or Field to each rung of the hierarchy). Every Field and Page object has a parent property, which points to the respective parent object of the other type. This is not a problem unless the parent-child mechanism is controlled by the base class (Pield), which is shared by the two descended classes (Page and Field). Here is one try, that fails at the line "Pield child = new Pield(pchild, this);": class Pield<T> { private T _pield_parent; ... private void get_children() { ... Pield<Page> child = new Pield<Page>(pchild, this); ... } ... } class Page : Pield<Field> { ... } class Field : Pield<Page> { ... } Any ideas about how to solve this elegantly? Best, Millicent

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  • What is the "un-tab" sequence in (g)Vim?

    - by OwenP
    This is an annoyance I've had for a long time. (Nitpicky section: I prefer 4 space characters to tab characters. It's a lot easier to type "tab" instead of explaining that. When I say "tab", I mean "the action that happens when you press the tab key" which is probably more simply stated as "increase indentation".) I'm using smartindent while editing a document where indentation has some significance. In "dumb" windows text editors I can press Shift+Tab to remove a tab or, more appropriately, decrease the indentation level of the current line. I can't figure out how to do this from edit mode in Vim; Shift+Tab seems to count just the same as Tab. I know in Command mode << will decrease indentation. I want the equivalent in edit mode. These are the solutions I've found so far and why I don't like them, one in particular may be the key to the answer. Use Notepad++ or some other dumb editor. I've done this for a couple of years but I really miss Vim. Exit edit mode, use <<, enter edit mode. This just puts the cursor at column 0; if I wanted this I wouldn't have tried smartindent. Stop using smartindent. I don't decrease indent as often as I need to keep the same indent level; this would be a loss of productivity. The left arrow key seems to decrease the indent by one level. I'd rather something I can do without leaving the home row. This is the most promising choice. Maybe there's an option I can set? Maybe I can rebind left arrow to something? (If it requires rebinding please explain in detail; I've never delved into reconfiguring (g)Vim.

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  • Separating code logic from the actual data structures. Best practices?

    - by Patrick
    I have an application that loads lots of data into memory (this is because it needs to perform some mathematical simulation on big data sets). This data comes from several database tables, that all refer to each other. The consistency rules on the data are rather complex, and looking up all the relevant data requires quite some hashes and other additional data structures on the data. Problem is that this data may also be changed interactively by the user in a dialog. When the user presses the OK button, I want to perform all the checks to see that he didn't introduce inconsistencies in the data. In practice all the data needs to be checked at once, so I cannot update my data set incrementally and perform the checks one by one. However, all the checking code work on the actual data set loaded in memory, and use the hashing and other data structures. This means I have to do the following: Take the user's changes from the dialog Apply them to the big data set Perform the checks on the big data set Undo all the changes if the checks fail I don't like this solution since other threads are also continuously using the data set, and I don't want to halt them while performing the checks. Also, the undo means that the old situation needs to be put aside, which is also not possible. An alternative is to separate the checking code from the data set (and let it work on explicitly given data, e.g. coming from the dialog) but this means that the checking code cannot use hashing and other additional data structures, because they only work on the big data set, making the checks much slower. What is a good practice to check user's changes on complex data before applying them to the 'application's' data set?

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  • need help understanding a function.

    - by Adam McC
    i had previously asked for help writing/improving a function that i need to calculate a premium based on differing values for each month. the premium is split in to 12 months and earned on a percentage for each month. so if the policy start in march and we are in jan we will have earned 10 months worth. so i need to add up the monthly earning to give us the total earned. wach company wil have differeing earnings values for each month. my original code is Here. its ghastly and slow hence the request for help. and i was presented with the following code. the code works but returns stupendously large figures. begin set @begin=datepart(month,@outdate) set @end=datepart(month,@experiencedate) ;with a as ( select *, case calmonth when 'january' then 1 when 'february' then 2 when 'march' then 3 when 'april' then 4 when 'may' then 5 when 'june' then 6 when 'july' then 7 when 'august' then 8 when 'september' then 9 when 'october' then 10 when 'november' then 11 when 'december' then 12 end as Mnth from tblearningpatterns where clientname=@client and earningpattern=@pattern ) , b as ( select earningvalue, Mnth, earningvalue as Ttl from a where Mnth=@begin union all select a.earningvalue, a.Mnth, cast(b.Ttl*a.earningvalue as decimal(15,3)) as Ttl from a inner join b on a.Mnth=b.Mnth+1 where a.Mnth<=@end ) select @earningvalue= Ttl from b inner join ( select max(Mnth) as Mnth from b ) c on b.Mnth=c.Mnth option(maxrecursion 12) SET @earnedpremium = @earningvalue*@premium end can someone please help me out?

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  • Is there any good reason for private methods existence in C# (and OOP in general)?

    - by Piotr Lopusiewicz
    I don't mean to troll but I really don't get it. Why would language designers allow private methods instead of some naming convention (see __ in Python) ? I searched for the answer and usual arguments are: a) To make the implementation cleaner/avoid long vertical list of methods in IDE autocompletion b) To announce to the world which methods are public interface and which may change and are just for implementation purpose c) Readability Ok so now, all of those could be achieved by naming all private methods with __ prefix or by "private" keyword which doesn't have any implications other than be information for IDE (don't put those in autocompletion) and other programers (don't use it unless you really must). Hell, one could even require unsafe-like keyword to access private methods to really discourage this. I am asking this because I work with some c# code and I keep changing private methods to public for test purposes as many in-between private methods (like string generators for xml serialization) are very useful for debugging purposes (like writing some part of string to log file etc.). So my question is: Is there anything which is achieved by access restriction but couldn't be achieved by naming conventions without restricting the access ?

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  • Migrating just article contect of Joomla 1.0 to 2.5.x / 3.x?

    - by user2919408
    I have a simple website using Joomla 1.0.15, just having articles in some categories. As i want to install or remove components from admin area, i got : "You are not authorised to view this resource" or something like that. This is uncommon, this site is about 5 years old, and never got error message like that. I think my website is hacked ?? I have set safe_mode = off in php.ini, turn of sh404sef, removing .htaccess file etc ... and it still does not work. Then i try to upgrade to Joomla 2.5.x / 3.x . I found that i must migrate to Joomla 1.5.x first, then from there to 2.5.x. I got problem installing "migration.zip" component in my Joomla 1.0.x (always alert/err message pop up is shown). Is there another way to migrate the website ? May be just get the article section, category, article id and the content of Joomla 1.0.x , then import it to Joomla 2.5.x / 3.x ? I don't need components, modules, mambots (if any) of the old site. How to do it ? Thanks

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  • (Java) Is there a type of object that can handle anything from primitives to arrays?

    - by Michael
    I'm pretty new to Java, so I'm hoping one of you guys knows how to do this. I'm having the user specify both the type and value of arguments, in any XML-like way, to be passed to methods that are external to my application. Example: javac myAppsName externalJavaClass methodofExternalClass [parameters] Of course, to find the proper method, we have to have the proper parameter types as the method may be overloaded and that's the only way to tell the difference between the different versions. Parameters are currently formatted in this manner: (type)value(/type), e.g. (int)71(/int) (string)This is my string that I'm passing as a parameter!(/string) I parse them, getting the constructor for whatever type is indicated, then execute that constructor by running its method, newInstance(<String value>), loading the new instance into an Object. This works fine and dandy, but as we all know, some methods take arrays, or even multi-dimensional arrays. I could handle the argument formatting like so: (array)(array)(int)0(/int)(int)1(/int)(/array)(array)(int)2(/int)(int)3(/int)(/array)(/array)... or perhaps even better... {{(int)0(/int)(int)1(/int)}{(int)2(/int)(int)3(/int)}}. The question is, how can this be implemented? Do I have to start wrapping everything in an Object[] array so I can handle primitives, etc. as argObj[0], but load an array as I normally would? (Unfortunately, I would have to make it an Object[][] array if I wanted to support two-dimensional arrays. This implementation wouldn't be very pretty.)

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  • How do I sort an activerecord result set on a i18n translated column?

    - by PlanetMaster
    Hi, I have the following line in a view: <%= f.select(:province_id, options_from_collection_for_select(Province.find(:all, :conditions => { :country_id => @property.country_id }, :order => "provinces.name ASC"), :id, :name) %> In the province model I have the following: def name I18n.t(super) end Problem is that the :name field is translated (through the province model) and that the ordering is done by activerecord on the english name. The non-english result set can be wrongly sorted this way. We have a province in Belgium called 'Oost-Vlaanderen'. In english that is 'East-Flanders". Not good for sorting:) I need something like this, but it does not work: <%= f.select(:province_id, options_from_collection_for_select(Province.find(:all, :conditions => { :country_id => @property.country_id }, :order => "provinces.I18n.t(name) ASC"), :id, :name) %> What would be the best approach to solve this? As you may have noticed, my coding knowledge is very limited, sorry for that.

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  • counter_cache not updating on the model after save

    - by sehnsucht
    I am using a counter_cache to let MySQL do some of the bookkeeping for me: class Container has_many :items end class Item belongs_to :container, :counter_cache => true end Now, if I do this: container = Container.find(57) item = Item.new item.container = container item.save in the SQL log there will be an INSERT followed by something like: UPDATE `containers` SET `items_count` = COALESCE(`items_count`, 0) + 1 WHERE `containers`.`id` = 57 which is what I expected it to do. However, the container[:items_count] will be stale! ...unless I container.reload to pick up the updated value. Which in my mind sort of defeats part of the purpose of using the :counter_cache in favor of a custom built one, especially since I may not actually want a reload before I try to access the items_count attribute. (My models are pretty code-heavy because of the nature of the domain logic, so I sometimes have to save and create multiple things in one controller call.) I understand I can tinker with callbacks myself but this seems to me a fairly basic expectation of the simple feature. Again, if I have to write additional code to make it fully work, it might as well be easier to implement a custom counter. What am I doing/assuming wrong?

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  • Sending a message to nil?

    - by Ryan Delucchi
    As a Java developer who is reading Apple's Objective-C 2.0 documentation: I wonder as to what sending a message to nil means - let alone how it is actually useful. Taking an excerpt from the documentation: There are several patterns in Cocoa that take advantage of this fact. The value returned from a message to nil may also be valid: If the method returns an object, any pointer type, any integer scalar of size less than or equal to sizeof(void*), a float, a double, a long double, or a long long, then a message sent to nil returns 0. If the method returns a struct, as defined by the Mac OS X ABI Function Call Guide to be returned in registers, then a message sent to nil returns 0.0 for every field in the data structure. Other struct data types will not be filled with zeros. If the method returns anything other than the aforementioned value types the return value of a message sent to nil is undefined. Has Java rendered my brain incapable of grokking the explanation above? Or is there something that I am missing that would make this as clear as glass? Note: Yes, I do get the idea of messages/receivers in Objective-C, I am simply confused about a receiver that happens to be nil.

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