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  • Migrating from CPython to Jython

    - by itsadok
    I'm considering moving my code (around 30K LOC) from CPython to Jython, so that I could have better integration with my java code. Is there a checklist or a guide I should look at, to help my with the migration? Does anyone have experience with doing something similar? From reading the Jython site, most of the problems seem too obscure to bother me. I did notice that: thread safety is an issue Unicode support seems to be quite different, which may be a problem for me mysqldb doesn't work and needs to be replaced with zxJDBC Anything else? Related question: What are some strategies to write python code that works in CPython, Jython and IronPython

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  • Building a Drupal Newsletter Module for handling Newsletter Articles

    - by Michael T. Smith
    We're building a module for generating HTML for email newsletters. We've looked into using a few other modules (SimpleNews, MailChimp, among others), but due to various requirements, it'll be easier and better for us to build a custom solution. Being a new Drupal developer, I'm a bit worried about handling this in a "non-Drupal" way. That being said, my plan is to setup a vocabulary with Newsletters as a term and the actual Newsletters as sub-terms, like so: Newsletters (term) - Newsletter A (sub-term) - Newsletter B (sub-term) This has the added benefit of being able to organize where articles were published (besides just on the site.) The question, though, is how to handle the different Newsletter issues. I could go another level deeper in the vocabulary, like so: Newsletters (term) - Newsletter A (sub-term) - Issue - 2010-03-01 - Issue - 2010-03-02 - Newsletter B (sub-term) - Issue - 2010-03-01 - Issue - 2010-03-08 But I'm wondering if this is adding a bit too much complexity. Once I have this taxonomy setup, when the user went to add new newsletters it would also create a node (content type: newsletter), and when he/she went to add new issues, it would also create a node (content type: issue.) Those would then be the landing pages for that content. So, the question is is there a better way for handling this structure? Is this a Drupal-like solution?

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  • Lisp Style question label local functions or not?

    - by Andrew Myers
    I was wondering if there is a standard practice regarding the use of labels in Lisp. I've been messing around with a Lisp implementation of the algorithm described in the first answer here http://stackoverflow.com/questions/352203/generating-permutations-lazily My current version uses labels to break out portions of functionality. (defun next-permutation (pmute) (declare (vector pmute)) (let ((len (length pmute))) (if (> len 2) (labels ((get-pivot () (do ((pivot (1- len) (1- pivot))) ((or (= pivot 0) (< (aref pmute (1- pivot)) (aref pmute pivot))) pivot))) (get-swap (pivot) (let ((swp (1- len))) (loop for i from (1- len) downto pivot do (if (or (and (> (aref pmute i) (aref pmute (1- pivot))) (< (aref pmute i) (aref pmute swp))) (< (aref pmute swp) (aref pmute (1- pivot)))) (setf swp i))) swp)) (next (swp pivot) (rotatef (aref pmute (1- pivot)) (aref pmute swp)) (reverse-vector pmute pivot (1- len)))) (let ((piv (get-pivot))) (if (> piv 0) (next (get-swap piv) piv) nil)))))) Since each label is only called once I was wondering if this is considered bad practice since the only reason to do it in this case is for aesthetic reasons. I would argue that the current version with labels is clearer but that may go against common wisdom that I'm not aware of, being new to Lisp.

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  • Connection Error using NHibernate 3.0 with Oracle

    - by Olu Lawrence
    I'm new to NHibernate. My first attempt is to configure and establish connection to Oracle 11.1g using ODP. For this test, I use a test fixture, but I get the following error: Inner exception: "Object reference not set to an instance of an object." Outer exception: Could not create the driver from NHibernate.Driver.OracleDataClientDriver. The test script is shown below: using IBCService.Models; using NHibernate.Cfg; using NHibernate.Tool.hbm2ddl; using NUnit.Framework; namespace IBCService.Tests { [TestFixture] public class GenerateSchema_Fixture { [Test] public void Can_generate_schema() { var cfg = new Configuration(); cfg.Configure(); cfg.AddAssembly(typeof(Product).Assembly); var fac = new SchemaExport(cfg); fac.Execute(false, true, false); } } } The exception occurs at the last line: fac.Execute(false, true, false); The NHibernate config is shown: <?xml version="1.0" encoding="utf-8"?> <!-- This config use Oracle Data Provider (ODP.NET) --> <hibernate-configuration xmlns="urn:nhibernate-configuration-2.2" > <session-factory name="IBCService.Tests"> <property name="connection.driver_class"> NHibernate.Driver.OracleDataClientDriver </property> <property name="connection.connection_string"> User ID=TEST;Password=test;Data Source=//RAND23:1521/RAND.PREVALENT.COM </property> <property name="connection.provider"> NHibernate.Connection.DriverConnectionProvider </property> <property name="show_sql">false</property> <property name="dialect">NHibernate.Dialect.Oracle10gDialect</property> <property name="query.substitutions"> true 1, false 0, yes 'Y', no 'N' </property> <property name="proxyfactory.factory_class"> NHibernate.ByteCode.LinFu.ProxyFactoryFactory, NHibernate.ByteCode.LinFu </property> </session-factory> </hibernate-configuration> Now, if I change the NHibernate.Driver.OracleDataClientDriver to NHibernate.Driver.OracleClientDriver (Microsoft provider for Oracle), the test succeed. Once switched back to Oracle provider, whichever version, the test fails with the error stated earlier. I've spent 3 days already trying to figure out what is not in order without success. I hope someone out there could provide useful info on what I am doing wrong.

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  • Perl unpack in list context

    - by drewk
    A common 'Perlism' is generating a list as something to loop over in this form: for($str=~/./g) { print "the next character from \"$str\"=$_\n"; } In this case the global match regex returns a list that is one character in turn from the string $str, and assigns that value to $_ Instead of a regex, split can be used in the same way or 'a'..'z', map, etc. I am investigating unpack to generate a field by field interpretation of a string. I have always found unpack to be less straightforward to the way my brain works, and I have never really dug that deeply into it. As a simple case, I want to generate a list that is one character in each element from a string using unpack (yes -- I know I can do it with split(//,$str) and /./g but I really want to see if unpack can be used this way...) Obviously, I can use a field list for unpack that is unpack("A1" x length($str), $str) but is there some other way that kinda looks like globbing? ie, can I call unpack(some_format,$str) either in list context or in a loop such that unpack will return the next group of character in the format group until $str is exausted? I have read The Perl 5.12 Pack pod and the Perl 5.12 pack tutorial and the Perkmonks tutorial Here is the sample code: #!/usr/bin/perl use warnings; use strict; my $str=join('',('a'..'z', 'A'..'Z')); #the alphabet... $str=~s/(.{1,3})/$1 /g; #...in groups of three print "str=$str\n\n"; for ($str=~/./g) { print "regex: = $_\n"; } for(split(//,$str)) { print "split: \$_=$_\n"; } for(unpack("A1" x length($str), $str)) { print "unpack: \$_=$_\n"; }

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  • Simple ASP.Net MVC 1.0 Validation

    - by Mike
    On the current project we are working on we haven't upgraded to MVC 2.0 yet so I'm working on implementing some simple validation with the tools available in 1.0. I'm looking for feedback on the way I'm doing this. I have a model that represents a user profile. Inside that model I have a method that will validate all the fields and such. What I want to do is pass a controller to the validation method so that the model can set the model validation property in the controller. The goal is to get the validation from the controller into the model. Here is a quick example public FooController : Controller { public ActionResult Edit(User user) { user.ValidateModel(this); if (ModelState.IsValid) ....... ....... } } And my model validation signature is like public void ValidateModel(Controller currentState) What issues can you see with this? Am I way out to lunch on how I want to do this?

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  • How can I effectively test a scripting engine?

    - by ChaosPandion
    I have been working on an ECMAScript implementation and I am currently working on polishing up the project. As a part of this, I have been writing tests like the following: [TestMethod] public void ArrayReduceTest() { var engine = new Engine(); var request = new ExecScriptRequest(@" var a = [1, 2, 3, 4, 5]; a.reduce(function(p, c, i, o) { return p + c; }); "); var response = (ExecScriptResponse)engine.PostWithReply(request); Assert.AreEqual((double)response.Data, 15D); } The problem is that there are so many points of failure in this test and similar tests that it almost doesn't seem worth it. It almost seems like my effort would be better spent reducing coupling between modules. To write a true unit test I would have to assume something like this: [TestMethod] public void CommentTest() { const string toParse = "/*First Line\r\nSecond Line*/"; var analyzer = new LexicalAnalyzer(toParse); { Assert.IsInstanceOfType(analyzer.Next(), typeof(MultiLineComment)); Assert.AreEqual(analyzer.Current.Value, "First Line\r\nSecond Line"); } } Doing this would require me to write thousands of tests which once again does not seem worth it.

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  • Java Builder pattern with Generic type bounds

    - by I82Much
    Hi all, I'm attempting to create a class with many parameters, using a Builder pattern rather than telescoping constructors. I'm doing this in the way described by Joshua Bloch's Effective Java, having private constructor on the enclosing class, and a public static Builder class. The Builder class ensures the object is in a consistent state before calling build(), at which point it delegates the construction of the enclosing object to the private constructor. Thus public class Foo { // Many variables private Foo(Builder b) { // Use all of b's variables to initialize self } public static final class Builder { public Builder(/* required variables */) { } public Builder var1(Var var) { // set it return this; } public Foo build() { return new Foo(this); } } } I then want to add type bounds to some of the variables, and thus need to parametrize the class definition. I want the bounds of the Foo class to be the same as that of the Builder class. public class Foo<Q extends Quantity> { private final Unit<Q> units; // Many variables private Foo(Builder<Q> b) { // Use all of b's variables to initialize self } public static final class Builder<Q extends Quantity> { private Unit<Q> units; public Builder(/* required variables */) { } public Builder units(Unit<Q> units) { this.units = units; return this; } public Foo build() { return new Foo<Q>(this); } } } This compiles fine, but the compiler is allowing me to do things I feel should be compiler errors. E.g. public static final Foo.Builder<Acceleration> x_Body_AccelField = new Foo.Builder<Acceleration>() .units(SI.METER) .build(); Here the units argument is not Unit<Acceleration> but Unit<Length>, but it is still accepted by the compiler. What am I doing wrong here? I want to ensure at compile time that the unit types match up correctly.

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  • Build and render infinite hierarchical category tree from self-referential category table

    - by FreshCode
    I have a Categories table in which each category has a ParentId that can refer to any other category's CategoryId that I want to display as multi-level HTML list, like so: <ul class="tree"> <li>Parent Category <ul> <li>1st Child Category <!-- more sub-categories --> </li> <li>2nd Child Category <!-- more sub-categories --> </li> </ul> </li> </ul> Presently I am recursively rendering a partial view and passing down the next category. It works great, but it's wrong because I'm executing queries in a view. How can I render the list into a tree object and cache it for quick display every time I need a list of all hierarchical categories?

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  • Large svn external

    - by MPelletier
    I have a project which uses a large library residing in its own repository. Using: Tortoise-SVN, the server is running an enterprise edition of VisualSVN The project itself has the "standard" structure: trunk tags branches In each branch, tag, and trunk is the library, set as an external (svn:external property). If I get the entire tree, I get the library several times, which is just getting too ridiculously repetitive. Is there a recommended structure for this? Or perhaps a way not to get all externals (because other externals are much smaller, easier to manipulate)?

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  • POJO's versus Cursors in Android

    - by Kilnr
    I usually tend to define the model layer of my apps using POJO's, such as Article, Comment, etc. I was about to implement an AlphabetIndexer in the adapter of one of my ListViews. Right now this adapter accepts a Collection of Articles, which I normally get from my wrapper around an SQLiteDatabase. The signature of the AlphabetIndexer constructer is as follows: public AlphabetIndexer (Cursor cursor, int sortedColumnIndex, CharSequence alphabet) Since this doesn't accept a Collection or something similar, just a Cursor, it got me wondering: maybe I shouldn't be creating objects for my model, and just use the Cursors returned from the database? So the question is, I guess: what should I do, represent data with Collections of POJO's, or just work with Cursors throughout my app? Any input?

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  • Why use Python interactive mode?

    - by mvid
    When I first started reading about Python, all of the tutorials have you use Python's Interactive Mode. It is difficult to save, write long programs, or edit your existing lines (for me at least). It seems like a far more difficult way of writing Python code than opening up a code.py file and running the interpreter on that file. python code.py I am coming from a Java background, so I have ingrained expectations of writing and compiling files for programs. I also know that a feature would not be so prominent in Python documentation if it were not somehow useful. So what am I missing?

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  • StringLengthValidator - localization not working

    - by danysdragons
    I am validating input to my ASP.NET application using StringLengthValidators, and using the ValidationSummary control to display the error messages. To localize the application, the StringLengthValidators have the MessageTemplateResourceName and MessageTemplateResourceType attributes set. The first time the validator runs, it picks up the correct error message based on the current culture setting. If I change the language setting while running the app, the next time the validator runs, the ValidationSummary it still displays the error message for the old culture. The text for all other controls is being updated correctly. Any ideas, folks?

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  • Dynamic State Machine in Ruby? Do State Machines Have to be Classes?

    - by viatropos
    Question is, are state machines always defined statically (on classes)? Or is there a way for me to have it so each instance of the class with has it's own set of states? I'm checking out Stonepath for implementing a Task Engine. I don't really see the distinction between "states" and "tasks" in there, so I'm thinking I could just map a Task directly to a state. This would allow me to be able to define task-lists (or workflows) dynamically, without having to do things like: aasm_event :evaluate do transitions :to => :in_evaluation, :from => :pending end aasm_event :accept do transitions :to => :accepted, :from => :pending end aasm_event :reject do transitions :to => :rejected, :from => :pending end Instead, a WorkItem (the main workflow/task manager model), would just have many tasks. Then the tasks would work like states, so I could do something like this: aasm_initial_state :initial tasks.each do |task| aasm_state task.name.to_sym end previous_state = nil tasks.each do |tasks| aasm_event task.name.to_sym do transitions :to => "#{task.name}_phase".to_sym, :from => previous_state ? "#{task.name}_phase" : "initial" end previous_state = state end However, I can't do that with the aasm gem because those methods (aasm_state and aasm_event) are class methods, so every instance of the class with that state machine has the same states. I want it so a "WorkItem" or "TaskList" dynmically creates a sequence of states and transitions based on the tasks it has. This would allow me to dynamically define workflows and just have states map to tasks. Are state machines ever used like this?

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  • trouble accessing non-static functions from static functions in AS3

    - by Dogmatixed
    I have a class containing, among other things, a drop down menu. With the aim of saving space, and since the contents of the menu will never change, I've made a static DataProvider for the whole class that populates each instances menu. I was hoping to populate the list with actual functions like so: tmpArr.push({label:"Details...", funct:openDetailsMenu, args:""}); and then assign tmpArr to the DataProvider. Because the DataProvider is static the function that contains that code also needs to be static, but the functions in the array are non-static. At first it didn't seem like a problem, because when the user clicks on a menu item the drop down menu can call a non-static "executeFunction(funct, args)" on its parent. However, when I try to compile, the static function setting up the DataProvider it can't find the non-static functions being passed. If the compiler would just trust me the code would work fine! The simple solution is to just pass strings and use a switch statement to call functions based on that, but that's big, ugly, inelegant, and difficult to maintain, especially if something inherits from this class. The simpler solution is to just make the DataProvider non-static, but I'm wondering if anyone else has a good way of dealing with this? Making the static function able to see its non-static brethren? Thanks.

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  • Invoice Discount: Negative line items vs Internal properties

    - by FreshCode
    Should discount on invoice items and entire invoices be negative line items or separate properties of an invoice? In a similar question, Should I incorporate list of fees/discounts into an order class or have them be itemlines, the asker focuses more on orders than invoices (which is a slightly different business entity). Discount is proposed to be separate from order items since it is not equivalent to a fee or product and may have different reporting requirements. Hence, discount should not simply be a negative line item. Previously I have successfully used negative line items to clearly indicate and calculate discount, but this feels inflexible and inaccurate from a business perspective. Now I am opting to add discount to each line item, along with an invoice-wide discount. Is this the right way to do it? Should each item have its own discount amount and percentage? Domain Model Code Sample This is what my domain model, which maps to an SQL repository, looks like: public class Invoice { public int ID { get; set; } public Guid JobID { get; set; } public string InvoiceNumber { get; set; } public Guid UserId { get; set; } // user who created it public DateTime Date { get; set; } public decimal DiscountPercent { get; set; } // all lines discount %? public decimal DiscountAmount { get; set; } // all lines discount $? public LazyList<InvoiceLine> InvoiceLines { get; set; } public LazyList<Payment> Payments { get; set; } // for payments received public boolean IsVoided { get; set; } // Invoices are immutable. // To change: void -> new invoice. public decimal Total { get { return (1.0M - DiscountPercent) * InvoiceLines.Sum(i => i.LineTotal) - DiscountAmount; } } } public class InvoiceLine { public int ID { get; set; } public int InvoiceID { get; set; } public string Title { get; set; } public decimal Quantity { get; set; } public decimal LineItemPrice { get; set; } public decimal DiscountPercent { get; set; } // line discount %? public decimal DiscountAmount { get; set; } // line discount amount? public decimal LineTotal { get { return (1.0M - DiscountPercent) * (this.Quantity * (this.LineItemPrice)) - DiscountAmount; } } }

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  • How to secure Add child record functionality in MVC on Parent's view?

    - by RSolberg
    I'm trying to avoid some potential security issues as I expose some a new set of functionality into the real world. This is basically functionality that will allow for a new comment to be added via a partialview on the "Parent" page. My comment needs to know a couple of things, first what record is the comment for and secondly who is making the comment. I really don't like using a hidden field to store the ID for the Parent record in the add comment form as that can be easily changed with some DOM mods. How should I handle this? PARENT <% Html.RenderPartial("AddComment", Model.Comments); %> CHILD <%@ Control Language="C#" Inherits="System.Web.Mvc.ViewUserControl<CommentsViewModel>" %> <% using (Html.BeginForm("AddComment", "Requests")) {%> <fieldset> <legend>New Comment</legend> <%= Html.HiddenFor(p => p.RequestID) %> <%= Html.TextBoxFor(p => p.Text) %> &nbsp; <input type="submit" value="Add" /> </fieldset> <% } %> CONTROLLER [AcceptVerbs(HttpVerbs.Post)] public void AddComment(CommentsViewModel commentsModel) { var user = GetCurrentUser(); commentsModel.CreatedByID = user.UserID; RequestsService.AddComment(commentsModel); }

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  • What is the recommended coding style for PowerShell?

    - by stej
    Is there any recommended coding style how to write PowerShell scripts? It's not about how to structure the code (how many functions, if to use module, ...). It's about 'how to write the code so that it is readable'. In programming languages there are some recommended coding styles (what to indent, how to indent - spaces/tabs, where to make new line, where to put braces,...), but I haven't seen any suggestion for PowerShell. What I'm interested particularly in: How to write parameters function New-XYZItem ( [string] $ItemName , [scriptblock] $definition ) { ... (I see that it's more like 'V1' syntax) or function New-PSClass { param([string] $ClassName ,[scriptblock] $definition )... or (why to add empty attribute?) function New-PSClass { param([Parameter()][string] $ClassName ,[Parameter()][scriptblock] $definition )... or (other formatting I saw maybe in Jaykul's code) function New-PSClass { param( [Parameter()] [string] $ClassName , [Parameter()] [scriptblock] $definition )... or ..? How to write complex pipeline Get-SomeData -param1 abc -param2 xyz | % { $temp1 = $_ 1..100 | % { Process-somehow $temp1 $_ } } | % { Process-Again $_ } | Sort-Object -desc or (name of cmdlet on new line) Get-SomeData -param1 abc -param2 xyz | % { $temp1 = $_ 1..100 | % { Process-somehow $temp1 $_ } } | % { Process-Again $_ } | Sort-Object -desc | and what if there are -begin -process -end params? how to make it the most readable? Get-SomeData -param1 abc -param2 xyz | % -begin { init } -process { Process-somehow2 ... } -end { Process-somehow3 ... } | % -begin { } .... or Get-SomeData -param1 abc -param2 xyz | % ` -begin { init } ` -process { Process-somehow2 ... } ` -end { Process-somehow3 ... } | % -begin { } .... the indentitation is important here and what element is put on new line as well. I have covered only questions that come on my mind very frequently. There are some others, but I'd like to keep this SO question 'short'. Any other suggestions are welcome.

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  • Blueprint CSS and Separation of Presentation and Content When Designing Forms

    - by Merritt
    Is it possible to use Blueprint CSS and maintain a a respectable level of separation between presentation and content? I like how easy the framework is to use when designing forms, but am worried that the manner in which I use the css classes for columnizing elements is a bad practice. For instance, say I have a 3 field form designed using blueprint: <div class="container"> <form action="" method="post" class="inline"> <fieldset> <legend>Example</legend> <div class="span-3"> <label for="a">Label A:</label> <input type="text" class="text" id="a" name="a" > </div> <div class="span-2"> <label for="b">Label B:</label> <input type="text" class="text" id="b" name="b" > </div> <div class="span-3"> <label for="o">Label O:</label> <input type="checkbox" id="o" name="o" value="true" checked="checked" class="checkbox">checkbox one </div> <div class="span-2 last"> <input type="submit" value="submit" class="button"> </div> </fieldset> </form> </div> Is using a class attribute with names like "span-2", "inline", and "last" a bad practice? Or am I missing the point?

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  • C# using namespace directive in nested namespaces

    - by MoSlo
    Right, I've usually used 'using' directives as follows using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace AwesomeLib { //awesome award winning class declarations making use of Linq } i've recently seen examples of such as using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace AwesomeLib { //awesome award winning class declarations making use of Linq namespace DataLibrary { using System.Data; //Data access layers and whatnot } } Granted, i understand that i can put USING inside of my namespace declaration. Such a thing makes sense to me if your namespaces are in the same root (they organized). System; namespace 1 {} namespace 2 { System.data; } But what of nested namespaces? Personally, I would leave all USING declarations at the top where you can find them easily. Instead, it looks like they're being spread all over the source file. Is there benefit to the USING directives being used this way in nested namespaces? Such as memory management or the JIT compiler?

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  • Are endless loops in bad form?

    - by rlbond
    So I have some C++ code for back-tracking nodes in a BFS algorithm. It looks a little like this: typedef std::map<int> MapType; bool IsValuePresent(const MapType& myMap, int beginVal, int searchVal) { int current_val = beginVal; while (true) { if (current_val == searchVal) return true; MapType::iterator it = myMap.find(current_val); assert(current_val != myMap.end()); if (current_val == it->second) // end of the line return false; current_val = it->second; } } However, the while (true) seems... suspicious to me. I know this code works, and logically I know it should work. However, I can't shake the feeling that there should be some condition in the while, but really the only possible one is to use a bool variable just to say if it's done. Should I stop worrying? Or is this really bad form. EDIT: Thanks to all for noticing that there is a way to get around this. However, I would still like to know if there are other valid cases.

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  • Web scraping etiquette

    - by Ash
    I'm considering writing a simple web scraping application to extract information from a website that does not seem to specifically prohibit this. I've checked for other alternatives (eg RSS, web service) to get this information, but there are none available at this stage. Despite this I've also developed/maintained a few websites myself and so I realize that if web scraping is done naively/greedily it can slow things down for other users and generally become a nuisance. So, what etiquette is involved in terms of: Number of requests per second/minute/hour. HTTP User Agent content. HTTP Referer content. HTTP Cache settings. Buffer size for larger files/resources. Legalities and licensing issues. Good tools or design approaches to use. Robots.txt, is this relevant for web scraping or just crawlers/spiders? Compression such as GZip in requests. Update Found this relevant question on Meta: Etiquette of Screen Scaping StackOverflow. Jeff Atwood's answer has some helpful recommendations. Other related StackOverflow questions: Options for html scraping Legalities of screen scraping

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  • Java enums vs constants for Strings

    - by Marcus
    I've switched from using constants for Strings: public static final String OPTION_1 = "OPTION_1"; ... to enums: public enum Options { OPTION_1; } With constants, you'd just refer to the constant: String s = TheClass.OPTION_1 But with Enums, you have to specify toString(): String s = Options.OPTION_1.toString(); I don't like that you have to use the toString() statement, and also, in some cases you can forget to include it which can lead to unintended results.. ie: Object o = map.get(Options.OPTION_1); //This won't work as intended if the Map key is a String Is there a better way to use enums for String constants?

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  • Why are floating point values so prolific?

    - by Kibbee
    So, title says it all. Why are floating point values so prolific in computer programming. Due to problems like rounding errors, and not being able to even accurately represent numbers such as 0.1, I really can't see how they got as far as they did. I understand that the computation is faster with floating point numbers, however, I can think of only a few cases that they actually the right data type would be using. If you sat back and think about every time you used a floating point value, how many times did you say, well, some error would be ok, as long as the result was a few microseconds faster. It really makes me think because Jeff was talking about NP completeness, and how heuristics give an answer that is kind of right. And well, computers shouldn't do that. They should give you the answer that is correct. Yet we see floating point values used in many applications where they are completely not valid. What really bugs me, isn't that floating point exists, but that in many languages, there isn't even a viable alternative, non-floating point, decimal value. A lot of programmers when doing financial applications have to fall back to storing the number of cents in an integer field. Which brings with it all kinds of other problems. Why do floats continue to be so prolific, even though they can't represent the real answer, and we expect computers to be accurate? [EDIT] Just to clarify, I was talking about Base 2 floating points, and not base 10 floating points. .Net offers the Decimal data type, which is a base 10 floating point value which offers a much better representation of the numbers we deal with on a daily basis in most computer programs. I find it hard to believe that even modern languages like Java don't support base 10 floating point values, unless you want to move into the realm of things like BigDecimal, which isn't really the right answer either in a lot of situations.

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