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  • MyContainer derived from FrameworkElement with binding support.

    - by alex2k8
    To understand how the binding works, I implemented MyContainer derived from FrameworkElement. This container allowes to set Children and adds them into the logical tree. But the binding by ElementName does not work. What can I do with MyContainer to make it work, leaving the parent as FrameworkElement? C#: public class MyContainer : FrameworkElement { public MyContainer() { Children = new List<FrameworkElement>(); } public List<FrameworkElement> Children { get; set; } protected override IEnumerator LogicalChildren { get { return Children.GetEnumerator(); } } } XAML: <Window x:Class="WpfLogicalTree.Window1" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:local="clr-namespace:WpfLogicalTree" Title="Window1" Height="300" Width="300"> <StackPanel> <local:MyContainer> <local:MyContainer.Children> <TextBlock Text="Foo" x:Name="_source" /> <TextBlock Text="{Binding Path=Text, ElementName=_source}" x:Name="_target"/> </local:MyContainer.Children> </local:MyContainer> <Button Click="Button_Click">Test</Button> </StackPanel> </Window> Window1.cs private void Button_Click(object sender, RoutedEventArgs e) { MessageBox.Show(_target.Text); }

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  • Perl - how to get the number of elements in a list (not a named array)

    - by NXT
    Hi Everyone, I'm trying to get a block of code down to one line. I need a way to get the number of items in a list. My code currently looks like this: # Include the lib directory several levels up from this directory my @ary = split('/', $Bin); my @ary = @ary[0 .. $#ary-4]; my $res = join '/',@ary; lib->import($res.'/lib'); That's great but I'd like to make that one line, something like this: lib->import( join('/', ((split('/', $Bin)) [0 .. $#ary-4])) ); But of course the syntax $#ary is meaningless in the above line. Is there equivalent way to get the number of elements in an anonymous list? Thanks! PS: The reason for consolidating this is that it will be in the header of a bunch of perl scripts that are ancillary to the main application, and I want this little incantation to be more cut & paste proof.

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  • How can I update a record using a correlated subquery?

    - by froadie
    I have a function that accepts one parameter and returns a table/resultset. I want to set a field in a table to the first result of that recordset, passing in one of the table's other fields as the parameter. If that's too complicated in words, the query looks something like this: UPDATE myTable SET myField = (SELECT TOP 1 myFunctionField FROM fn_doSomething(myOtherField) WHERE someCondition = 'something') WHERE someOtherCondition = 'somethingElse' In this example, myField and myOtherField are fields in myTable, and myFunctionField is a field return by fn_doSomething. This seems logical to me, but I'm getting the following strange error: 'myOtherField' is not a recognized OPTIMIZER LOCK HINTS option. Any idea what I'm doing wrong, and how I can accomplish this? *UPDATE: * Based on Anil Soman's answer, I realized that the function is expecting a string parameter and the field being passed is an integer. I'm not sure if this should be a problem as an explicit call to the function using an integer value works - e.g. fn_doSomething(12345) seems to automatically cast the number to an string. However, I tried to do an explicit cast: UPDATE myTable SET myField = (SELECT TOP 1 myFunctionField FROM fn_doSomething(CAST(myOtherField AS varchar(1000))) WHERE someCondition = 'something') WHERE someOtherCondition = 'somethingElse' Now I'm getting the following error: Line 5: Incorrect syntax near '('.

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  • [PHP] Weird problem with dynamic method invocation

    - by Rolf
    Hi everyone, this time, I'm facing a really weird problem. I've the following code: $xml = simplexml_load_file($this->interception_file); foreach($xml->children() as $class) { $path = str_replace('__CLASS_DIR__',CLASS_DIR,$class['path']); if(!is_file($path)) { throw new Exception('Bad configuration: file '.$path.' not found'); } $className = pathinfo($path,PATHINFO_FILENAME); foreach($class as $method) { $method_name = $method['name']; $obj = new $className(); var_dump(in_array($method_name,get_class_methods($className)));exit; echo $obj->$method_name();### not a method ??? } } As you can see, I get the class name and method name from an XML file. I can create an instance of the class without any problem. The var_dump at the end returns true, that means $method_name (which has 2 optional parameters) is a method of $className. BUT, and I am pretty sure the syntax is correct, when I try: $obj-$method_name() I get: Fatal error: Method name must be a string If you have any ideas, pleaaaaase tell me :) Thanks in advance, Rolf

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  • Passing in a lambda to a Where statement

    - by sonicblis
    I noticed today that if I do this: var items = context.items.Where(i => i.Property < 2); items = items.Where(i => i.Property > 4); Once I access the items var, it executes only the first line as the data call and then does the second call in memory. However, if I do this: var items = context.items.Where(i => i.Property < 2).Where(i => i.Property > 4); I get only one expression executed against the context that includes both where statements. I have a host of variables that I want to use to build the expression for the linq lambda, but their presence or absence changes the expression such that I'd have to have a rediculous number of conditionals to satisfy all cases. I thought I could just add the Where() statements as in my first example above, but that doesn't end up in a single expression that contains all of the criteria. Therefore, I'm trying to create just the lambda itself as such: //bogus syntax if (var1 == "something") var expression = Expression<Func<item, bool>>(i => i.Property == "Something); if (var2 == "somethingElse") expression = expression.Where(i => i.Property2 == "SomethingElse"); And then pass that in to the where of my context.Items to evaluate. A) is this right, and B) if so, how do you do it?

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  • Checking if Date is within Range

    - by Brett Powell
    So I am using a scripting language with c++ syntax, and trying to think of the best way to check if a date is within range. The problem I am running into is that if the current day is in a new month, the check is failing. Here is what my code looks like... if(iMonth >= iStartMonth && iMonth <= iEndMonth) { if(iDay >= iStartDay && iDay <= iEndDay) { if(iYear >= iStartYear && iYear <= iEndYear) { bEnabled = true; return; When I have something like this... (Pulled in from cfg file specified by client) Start date: 3 27 2010 End Date: 4 15 2010 Current Date: 3 31 2010 The day check fails because if(iDay <= iEndDay) does not pass. The scripting language doesn't have a lot of time related functions, and I cant compare timestamps because im allowing users to put like "03:27:2010" and "04:15:2010" as start/end dates in a config file. Im assuming I am just not thinking straight and missing an easy fix.

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  • Newbie C# Question about float/int/text type formatting

    - by user563501
    Hey everybody, I'm a total C# newb with a light (first year CS) background in Python. I wrote a console program in Python for doing marathon pace running calculations and I'm trying to figure out the syntax for this in C# using Visual Studio 2010. Here's a chunk of what I've got so far: string total_seconds = ((float.Parse(textBox_Hours.Text) * 60 * 60) + (float.Parse(textBox_Minutes.Text) * 60) + float.Parse(textBox_Seconds.Text)).ToString(); float secs_per_unit = ((float)(total_seconds) / (float)(textBox_Distance.Text)); float mins_per_unit = (secs_per_unit / 60); string pace_mins = (int)mins_per_unit.ToString(); string pace_secs = (float.Parse(mins_per_unit) - int.Parse(mins_per_unit) * 60).ToString(); textBox_Final_Mins.Text = pace_mins; textBox_Final_Secs.Text = pace_mins; Imagine you have a running pace of 8 minutes and 30 seconds per mile. secs_per_unit would be 510, mins_per_unit would be 8.5. pace_mins would simply be 8 and pace_secs would be 30. In Python I'd just convert variables from a float to a string to get 8 instead of 8.5, for example; hopefully the rest of the code gives you an idea of what I've been doing. Any input would be appreciated.

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  • EXC_BAD_ACCESS with NSUserdefaults on iphone.

    - by Andreas Johannessen
    I have the following code in my ApplicationDelegate. My deployment target is 3.0 and upwards, however I get a EXC_BAD_ACCESS when I launch the app with the following code on my iPhone with 3.1.3, however on the simulator which has 4.2 it runs fine. I would really appriciate help on this one, thanks in advance. When I comment this block when I deploy to 3.1.3 device it runs without bad access. + (void)initialize { NSString *path = [[NSBundle mainBundle] bundlePath]; NSString *pListPath = [path stringByAppendingPathComponent:@"Settings.bundle/Root.plist"]; NSDictionary *pList = [NSDictionary dictionaryWithContentsOfFile:pListPath]; NSMutableArray *prefsArray = [pList objectForKey:@"PreferenceSpecifiers"]; NSMutableDictionary *regDictionary = [NSMutableDictionary dictionary]; for (NSDictionary *dict in prefsArray) { NSString *key = [dict objectForKey:@"Key"]; if(key) { id value = [dict objectForKey:@"DefaultValue"]; [regDictionary setObject:value forKey:key]; } } [[NSUserDefaults standardUserDefaults] registerDefaults:regDictionary]; } UPDATE: I traced the error to happen on this line: [[NSUserDefaults standardUserDefaults] registerDefaults:regDictionary]; So there is probaly another syntax on earlier iOS, or am I wrong?

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  • d2: assigning ranges/iterators to array slices

    - by modchan
    Consider following code: enum size = 16; double[size] arr1 = [...]; double[size] arr2 = [...]; process = (double x) { return (x + 1); }; arr2[] = map!(process)(arr1[]); // here I have trouble converting results of map back to my plain array. Problem applies not only to map, but also to take, repeat and all those fine tools from std.algorithm and std.range that operate on ranges. On this assignment, I get Error: cannot implicitly convert expression (map(arr1[])) of type Result to double[]. How can I evaluate range to array without using uint i = 0; foreach (x; map!(process)(arr1[])) { arr2[i] = x; i++; } ? Additionally, can someone please explain, why I must call map!(process)(arr1[]) instead of map!(process)(arr1) with static arrays? Shouldn't static arrays be compatible with dynamic for means of iteration, or I don't get something? Also, it seems that straightforward enumeration syntax foreach (index, item; sequence) does not work for ranges - are there workarounds? I guess the reason is the same as why ranges cannot be assigned to array slices.

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  • NHibernate query against the key field of a dictionary (map)

    - by Carl Raymond
    I have an object model where a Calendar object has an IDictionary<MembershipUser, Perms> called UserPermissions, where MembershipUser is an object, and Perms is a simple enumeration. This is in the mapping file for Calendar as <map name="UserPermissions" table="CalendarUserPermissions" lazy="true" cascade="all"> <key column="CalendarID"/> <index-many-to-many class="MembershipUser" column="UserGUID" /> <element column="Permissions" type="CalendarPermission" not-null="true" /> </map> Now I want to execute a query to find all calendars for which a given user has some permission defined. The permission is irrelevant; I just want a list of the calendars where a given user is present as a key in the UserPermissions dictionary. I have the username property, not a MembershipUser object. How do I build that using QBC (or HQL)? Here's what I've tried: ISession session = SessionManager.CurrentSession; ICriteria calCrit = session.CreateCriteria<Calendar>(); ICriteria userCrit = calCrit.CreateCriteria("UserPermissions.indices"); userCrit.Add(Expression.Eq("Username", username)); return calCrit.List<Calendar>(); This constructed invalid SQL -- the WHERE clause contained WHERE membership1_.Username = @p0 as expected, but the FROM clause didn't include the MemberhipUsers table. Also, I really had to struggle to learn about the .indices notation. I found it by digging through the NHibernate source code, and saw that there's also .elements and some other dotted notations. Where's a reference to the allowed syntax of an association path? I feel like what's above is very close, and just missing something simple.

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  • Determining polygon intersection and containment

    - by Victor Liu
    I have a set of simple (no holes, no self-intersections) polygons, and I need to check that they don't intersect each other (one can be entirely contained in another; that is okay). I can check this by simply checking the per-vertex inside-ness of one polygon versus other polygons. I also need to determine the containment tree, which is the set of relationships that say which polygon contains any given polygon. Since no polygon can intersect any other, then any contained polygon has a unique container; the "next-bigger" one. In other words, if A contains B contains C, then A is the parent of B, and B is the parent of C, and we don't consider A the parent of C. The question: How do I efficiently determine the containment relationships and check the non-intersection criterion? I ask this as one question because maybe a combined algorithm is more efficient than solving each problem separately. The algorithm should take as input a list of polygons, given by a list of their vertices. It should produce a boolean B indicating if none of the polygons intersect any other polygon, and also if B = true, a list of pairs (P, C) where polygon P is the parent of child C. This is not homework. This is for a hobby project I am working on.

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  • Setting up relations/mappings for a SQLAlchemy many-to-many database

    - by Brent Ramerth
    I'm new to SQLAlchemy and relational databases, and I'm trying to set up a model for an annotated lexicon. I want to support an arbitrary number of key-value annotations for the words which can be added or removed at runtime. Since there will be a lot of repetition in the names of the keys, I don't want to use this solution directly, although the code is similar. My design has word objects and property objects. The words and properties are stored in separate tables with a property_values table that links the two. Here's the code: from sqlalchemy import Column, Integer, String, Table, create_engine from sqlalchemy import MetaData, ForeignKey from sqlalchemy.orm import relation, mapper, sessionmaker from sqlalchemy.ext.declarative import declarative_base engine = create_engine('sqlite:///test.db', echo=True) meta = MetaData(bind=engine) property_values = Table('property_values', meta, Column('word_id', Integer, ForeignKey('words.id')), Column('property_id', Integer, ForeignKey('properties.id')), Column('value', String(20)) ) words = Table('words', meta, Column('id', Integer, primary_key=True), Column('name', String(20)), Column('freq', Integer) ) properties = Table('properties', meta, Column('id', Integer, primary_key=True), Column('name', String(20), nullable=False, unique=True) ) meta.create_all() class Word(object): def __init__(self, name, freq=1): self.name = name self.freq = freq class Property(object): def __init__(self, name): self.name = name mapper(Property, properties) Now I'd like to be able to do the following: Session = sessionmaker(bind=engine) s = Session() word = Word('foo', 42) word['bar'] = 'yes' # or word.bar = 'yes' ? s.add(word) s.commit() Ideally this should add 1|foo|42 to the words table, add 1|bar to the properties table, and add 1|1|yes to the property_values table. However, I don't have the right mappings and relations in place to make this happen. I get the sense from reading the documentation at http://www.sqlalchemy.org/docs/05/mappers.html#association-pattern that I want to use an association proxy or something of that sort here, but the syntax is unclear to me. I experimented with this: mapper(Word, words, properties={ 'properties': relation(Property, secondary=property_values) }) but this mapper only fills in the foreign key values, and I need to fill in the other value as well. Any assistance would be greatly appreciated.

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  • Users Hierarchy Logic

    - by user342944
    Hi guys, I am writing a user security module using SQLServer 2008 so threfore need to design a database accordingly. Formally I had Userinfo table with UserID, Username and ParentID to build a recursion and populated tree to represent hierarchy but now I have following criteria which I need to develop. I have now USERS, ADMINISTRATORS and GROUPS. Each node in the user hierarchy is either a user, administrator or group. User Someone who has login access to my application Administrator A user who may also manage all their child user accounts (and their children etc) This may include creating new users and assigning permissions to those users. There is no limit to the number of administrators in user structure. The higher up in the hierarchy that I go administrators have more child accounts to manage which include other child administrators. Group A user account can be designated as a group. This will be an account which is used to group one or more users together so that they can be manage as a unit. But no one can login to my application using a group account. This is how I want to create structure Super Administrator administrator ------------------------------------------------------------- | | | Manager A Manager B Manager C (adminstrator) (administrator) (administrator) | ----------------------------------------- | | | Employee A Employee B Sales Employees (User) (User) (Group) | ------------------------ | | | Emp C Emp D Emp E (User) (User) (User) Now how to build the table structure to achieve this. Do I need to create Users table alongwith Group table or what? Please guide I would really appreciate.

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  • How does XAML set readonly CLR properties

    - by Igor Zevaka
    I am trying to create an application bar in code for WinPhone7. The XAML that does it goes like this: <PhoneApplicationPage.ApplicationBar> <shellns:ApplicationBar Visible="True" IsMenuEnabled="True"> <shellns:ApplicationBar.Buttons> <shellns:ApplicationBarIconButton IconUri="/images/appbar.feature.search.rest.png" /> </shellns:ApplicationBar.Buttons> </shellns:ApplicationBar> </PhoneApplicationPage.ApplicationBar> So I thought I'd just rewrite it in C#: var appbar = new ApplicationBar(); var buttons = new List<ApplicationBarIconButton>(); buttons.Add(new ApplicationBarIconButton(new Uri("image.png", UrlKind.Relative)); appbar.Buttons = buttons; //error CS0200: Property or indexer 'Microsoft.Phone.Shell.ApplicationBar.Buttons' cannot be assigned to -- it is read only The only problem is that Buttons property does not have a set accessor and is defined like so: public sealed class ApplicationBar { //...Rest of the ApplicationBar class from metadata public IList Buttons { get; } } How come this can be done in XAML and not C#? Is there a special way that the objects are constructed using this syntax? More importantly, how can I recreate this in code?

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  • Find all CSS rules that apply to an element

    - by Carl Byström
    Many tools/APIs provide ways of selecting elements of specific classes or IDs. There's also possible to inspect the raw stylesheets loaded by the browser. However, for browsers to render an element, they'll compile all CSS rules (possibly from different stylesheet files) and apply it to the element. This is what you see with Firebug or the WebKit Inspector - the full CSS inheritance tree for an element. How can I reproduce this feature in pure JavaScript without requiring additional browser plugins? Perhaps an example can provide some clarification for what I'm looking for: <style type="text/css"> p { color :red; } #description { font-size: 20px; } </style> <p id="description">Lorem ipsum</p> Here the p#description element have two CSS rules applied: a red color and a font size of 20 px. I would like to find the source from where these computed CSS rules originate from (color comes the p rule and so on).

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  • Is there an application that can help someone create an XML document based on the Relax NG schema?

    - by meowsqueak
    I've spent a bit of time creating a Relax NG schema for use within our team to validate XML documents we use for exchanging information. The schema is not complicated, but it is reasonably large. I am wondering if there exists a tool that can read in such a Relax NG schema and assist a user in creating a corresponding instance document, using the schema as a template. Perhaps an application with a GUI that creates fields and drop-down selections for each part of the document? For example, the tool might create an outline XML document and prompt the user to select multiples of certain elements, fill in each field, perhaps with permitted values read directly from the schema. It might also show the user via visual feedback when their document is 'complete', or highlight validation problems as they come up. I could anticipate writing a custom GUI tool to create such an XML document, but I'd really like changes to the schema to be automatically reflected by the GUI - and I really wonder if this hasn't already been done. I know some editors can automatically validate an XML document against a schema as it's being written, but I would really like to get my users one step away from the XML so they don't have to worry about the details of the XML syntax.

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  • Component based web project directory layout with git and symlinks

    - by karlthorwald
    I am planning my directory structure for a linux/apache/php web project like this: Only www.example.com/webroot/ will be exposed in apache www.example.com/ webroot/ index.php comp1/ comp2/ component/ comp1/ comp1.class.php comp1.js comp2/ comp2.class.php comp2.css lib/ lib1/ lib1.class.php the component/ and lib/ directory will only be in the php path. To make the css and js files visible in the webroot directory I am planning to use symlinks. webroot/ index.php comp1/ comp1.js (symlinked) comp2/ comp2.css (symlinked) I tried following these principles: layout by components and libraries, not by file type and not by "public' or 'non public', index.php is an exception. This is for easier development. symlinking files that need to be public for the components and libs to a public location, but still mirroring the layout. So the component and library structure is also visible in the resulting html code in the links, which might help development. git usage should be safe and always work. it would be ok to follow some procedure to add a symlink to git, but after that checking them out or changing branches should be handled safely and clean How will git handle the symlinking of the single files correctly, is there something to consider? When it comes to images I will need to link directories, how to handle that with git? component/ comp3/ comp3.class.php img/ img1.jpg img2.jpg img3.jpg They should be linked here: webroot/ comp3/ img/ (symlinked ?) If using symlinks for that has disadvantages maybe I could move images to the webroot/ tree directly, which would break the first principle for the third (git practicability). So this is a git and symlink question. But I would be interested to hear comments about the php layout, maybe you want to use the comment function for this.

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  • How do I use .htaccess to redirect to a URL containing HTTP_HOST?

    - by Jon Cram
    Problem I need to redirect some short convenience URLs to longer actual URLs. The site in question uses a set of subdomains to identify a set of development or live versions. I would like the URL to which certain requests are redirected to include the HTTP_HOST such that I don't have to create a custom .htaccess file for each host. Host-specific Example (snipped from .htaccess file) Redirect /terms http://support.dev01.example.com/articles/terms/ This example works fine for the development version running at dev01.example.com. If I use the same line in the main .htaccess file for the development version running under dev02.example.com I'd end up being redirected to the wrong place. Ideal rule (not sure of the correct syntax) Redirect /terms http://support.{HTTP_HOST}/articles/terms/ This rule does not work and merely serves as an example of what I'd like to achieve. I could then use the exact same rule under many different hosts and get the correct result. Answers? Can this be done with mod_alias or does it require the more complex mod_rewrite? How can this be achieved using mod_alias or mod_rewrite? I'd prefer a mod_alias solution if possible. Clarifications I'm not staying on the same server. I'd like: http://example.com/terms/ - http://support.example.com/articles/terms/ https://secure.example.com/terms/ - http://support.example.com/articles/terms/ http://dev.example.com/terms/ - http://support.dev.example.com/articles/terms/ https://secure.dev.example.com/terms/ - http://support.dev.example.com/articles/terms/ I'd like to be able to use the same rule in the .htaccess file on both example.com and dev.example.com. In this situation I'd need to be able to refer to the HTTP_HOST as a variable rather than specifying it literally in the URL to which requests are redirected. I'll investigate the HTTP_HOST parameter as suggested but was hoping for a working example.

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  • How can I diff against a revision of a single file using only the default Git GUI tools?

    - by Rich
    I want to view the history of a single file, and then compare a single revision from that history against the current version. On the command line, this is easy: Run: git log -- <filename> Locate the version you want to compare, Run: git diff <commitid> -- <filename> But how can this be done using only the default Git gui tools, git gui and gitk? I know of two methods using gitk, but they're both horribly clunky: Either: Select the New View option from the View menu, Type in the full path to your file into the box labelled Enter files and directories to include, one per line, Locate the version you want to compare by looking at the highlighted items in the top pane, and click on it to select it, Right-click on the current version and select Diff selected - this, Or: Select Tree in the bottom right-hand pane, Locate the file you want to look at, right-click on it, and select Highlight this only, Locate the version you want to compare by looking at the highlighted items in the top pane, and click on it to select it, Right-click on the current version and select Diff selected - this, Click on the file in the bottom right-hand pane to jump to it in the diff output, or scroll manually. Is a better method than this?

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  • Manifesto for Integrated Development Environments

    - by Hugo S Ferreira
    Have you recently take a peek at Coda, or Espresso, or Textmate? Or even Google Chrome's Developer Tools? They are well designed, intuitive, interface rich, and extensible. But Coda, Espresso or Textmate, among several, are text editors, not IDEs. On the other side, VIM and Emacs live in the last century, and Eclipse is an overbloated platform. This is more like an outcry for a decent, common infrastructure for REAL IDEs. But there's some questions attached: (i) what features are needed for such a product and (ii) what products are out there that could fullfil this need, and what are they missing. So here's my draft for a manifesto: Manifesto for Integrated Development Environments: We favor interactivity and productivity over syntax and tools. We favor inline, contextual documentation over man and html files. We favor high-definition, graphic-capable color screens over 80x25 character terminals. We favor the use of advanced input schemas over unintuitive keyboard shortcuts. We favor a common, extensible and customizable infrastructure over unmaintained chaintools. We know the difference between search&replace and refactoring. We know the difference between integrated debugging support over a terminal window. We know the difference between semantic-aware code-completion over dumb textual templates. We favor the usage of standards like (E)BNF.

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  • Learning C++ as a Perl programmer

    - by meneldor
    Hello all, I'm a Perl5 programmer for 7 years and I'm trying to learn C++ now. Some of the c++ syntax is hard for me to understand and to think in c++ way. For example: In perl you can mix the data in the arrays @array = (1,"string",5.355); You can assign any value to a scalar variable: $var = 1; $var = "string"; $var = \$reference_to_scalar; There are many examples. The friend of mine recommend me the book "Thinking of C++" by Bruce Eckel, but I haven't any C background and it's hard for me to understand some things. So my question is - could you recommend me a book for this situation. I don't want to learn C. I understand OOP (I'm getting more familiar with C++ oop aswell), I understand the point of the pointers(and some arithmetic) and references(widely used in perl). I dont need some of the manuals for dummies (what is int,bool,double,if,while), I just need a direction how to learn C++ from my point of perl programmer, because I,m sure that there are many like me. Thank you in advance.

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  • Can someone tell me what this Java class does? I/O related

    - by anon
    I am relatively new to Java and trying to learn the I/O syntax. Could someone give me a general overview of what this code does? Thanks!! import java.io.*; public class FileReader { private String openFile=""; private String saveFile=""; FileReader(openFile, saveFile) { this.openFile=openFile; this.saveFile=saveFile; } public String process(){ System.out.println(this.openFile); System.out.println(this.saveFile); BufferedReader open=null; FileReader openFR=null; FileWriter save=null; int counter=0; String output=""; if(openFile.equals("")){ return "No open file specifified\n"; } if(this.saveFile.equals("")){ return "No save file specified\n"; } try { openFR = new FileReader(this.openFile); open = new BufferedReader(openFR); } catch (FileNotFoundException e) { return ("Open file no longer exists\n"); } try { save = new FileWriter(saveFile); } catch (IOException e){ return ("Error saving the file\n"); } try{ String temp = open.readLine(); while(temp != null){ temp = open.readLine(); counter++; save.write(output + "\n"); } } catch (IOException e){ e.getStackTrace(); return ("Error reading open file"); } try { save.flush(); } catch (IOException e) { e.printStackTrace(); return ("Error writing save file"); } return "Operation completed successfully"; } }

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  • install barnyard2 ubuntu 12.04

    - by Muhammad Ardiansyah
    I trying to install barnyard2 in ubuntu 12.04 32-bit I'm configure using syntax: ./configure --with-mysql-libraries=/usr/lib/x86_64-linux-gnu and when I trying to compile daq-1.1.1 using a makefile, I encountered the following errors: make[3]: Leaving directory /root/snortinstall/barnyard2/src' make[2]: Leaving directory/root/snortinstall/barnyard2/src' Making all in etc make[2]: Entering directory /root/snortinstall/barnyard2/etc' make[2]: Nothing to be done forall'. make[2]: Leaving directory /root/snortinstall/barnyard2/etc' Making all in doc make[2]: Entering directory/root/snortinstall/barnyard2/doc' make[2]: Nothing to be done for all'. make[2]: Leaving directory /root/snortinstall/barnyard2/doc' Making all in rpm make[2]: Entering directory /root/snortinstall/barnyard2/rpm' make[2]: Nothing to be done forall'. make[2]: Leaving directory /root/snortinstall/barnyard2/rpm' Making all in schemas make[2]: Entering directory/root/snortinstall/barnyard2/schemas' make[2]: Nothing to be done for all'. make[2]: Leaving directory /root/snortinstall/barnyard2/schemas' Making all in m4 make[2]: Entering directory /root/snortinstall/barnyard2/m4' make[2]: Nothing to be done forall'. make[2]: Leaving directory /root/snortinstall/barnyard2/m4' make[2]: Entering directory /root/snortinstall/barnyard2' make[2]: Nothing to be done for all-am'. make[2]: Leaving directory/root/snortinstall/barnyard2' make[1]: Leaving directory `/root/snortinstall/barnyard2'

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  • Trait, FunctionN, or trait-inheriting-FunctionN in Scala?

    - by Willis Blackburn
    I have a trait in Scala that has a single method. Call it Computable and the single method is compute(input: Int): Int. I can't figure out whether I should Leave it as a standalone trait with a single method. Inherit from (Int = Int) and rename "compute" to "apply." Just get rid of Computable and use (Int = Int). A factor in favor of it being a trait is that I could usefully add some additional methods. But of course if they were all implemented in terms of the compute method then I could just break them out into a separate object. A factor in favor of just using the function type is simplicity and the fact that the syntax for an anonymous function is more concise than that for an anonymous Computable instance. But then I've no way to distinguish objects that are actually Computable instances from other functions that map Int to Int but aren't meant to be used in the same context as Computable. How do other people approach this type of problem? No right or wrong answers here; I'm just looking for advice.

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  • how to store a file handle in perl class

    - by Haiyuan Zhang
    please look at the following code first. #! /usr/bin/perl package foo; sub new { my $pkg = shift; my $self = {}; my $self->{_fd} = undef; bless $self, $pkg; return $self; } sub Setfd { my $self = shift; my $fd = shift; $self_->{_fd} = $fd; } sub write { my $self = shift; print $self->{_fd} "hello word"; } my $foo = new foo; My intention is to store a file handle within a class using hash. the file handle is undefined at first, but can be initilized afterwards by calling Setfd function. then write can be called to actually write string "hello word" to a file indicated by the file handle, supposed that the file handle is the result of a success "write" open. but, perl compiler just complains that there are syntax error in the "print" line. can anyone of you tells me what's wrong here? thanks in advance.

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