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I am trying to learn Lisp and looking at all the Lisps out there and their differences.
I see that in some implementations of Scheme, you can use square brackets interchangeably with round brackets for readability, so because they are treated the same, I assume they are still just S-expressions like everything else.
Ho... |
I couldn't understand the reason of it. I always use String class like other developers, but when I modify the value of it, new instance of String created.
What might be the reason of immutability for String class in Java?
I know there are some alternatives like StringBuffer or StringBuilder. It's just curiosity.
|
How can I say in english, that programming language can be compiled to other programming languages?
The example can be Haxe. On the website the language is decribed as "Multiplatform":
Multiplatform:
Haxe can be compiled to all popular programming platforms with its
fast compiler – JavaScript, Flash, NekoVM, PHP, ... |
One of our team member duplicates code. Code duplication causes confusion among my team members reading his code, it causes bugs down the line when the duplicated segment is fixed in one location and not the others and it bloats the size of his code-base.
I have discussed with him not to duplicate code. But he show exc... |
I've been told in previous questions that functional programming languages are unsuited for dynamic systems such as a physics engine, mainly because it's costly to mutate objects. How realistic is this statement, and why?
|
What is it called when you aren't using an MVC framework and each URL has it's own file associated with it. I want to say it's model 0 or class 0 but I haven't been able to find anything useful via Google. :-)
|
As a DBA, most SQL is submitted to my team for review. We do not have a SQL developer, so the code is frequently very, very inefficient.
Our current process is:
SQL is submitted for review right before it goes to beta
Issues are pointed out but frequently not resolved because the application has already been written ... |
I know there are some products for reverse debugging.
I am wondering that does reverse debugging mean going to one step back or starting over again up to one step back?
I've found an explanation here.
|
I've been talking to a colleague that comes from AS3 to the HTML world. He has created a small website (there are apparently no dynamic contents) following the no-flash rules for his very first time, and as if you own a hammer you tend to hammer everything, he decided to create a framework in JavaScript, so he could do... |
Because we need to keep response times low, we get tons of requests, and we need to basically process ALMOST the same data (which I'll refer to as X) each request (the inputs are different though, so we can't cache responses), we are using a technique where we grab a new copy of X every 90 seconds from the database and... |
I have been in the process of generating documentation for an upcoming project. One of the features of the data available in this project is that it will be revisioned (or at least large parts of it will be).
I came across the (as I understand it, very new) "Accept-Datetime" HTTP header. This looks absolutely perfect f... |
I mostly work in Python and Ruby, but I recently decided to learn some C so I have a better feel for how a computer actually works.
I've been wondering whether it is possible to take this even a step further. Does anyone learn machine code (whatever C is compiled into) anymore? Would I benefit from taking some time to ... |
I am creating a stored procedure that is logging some data. The data ultimately needs to end up in 2 tables. The incoming data is coming from a JSON string containing 15 parameters, and the data is then logged to the database using the stored procedure I'm writing. I would like to send the data into 1 stored procedure ... |
I currently have a database that uses Class table inheritance model. Three different tables inherit from this table. The child tables have all a FK to the parent table and the fields are properly indexed.
We hare currently having some issues at the application level because it is difficult to figure out what child tab... |
In C#/Java, the dependency inversion principle is often demonstrated by high-level classes that depends on an interface/abstraction (that it owns). Low-level classes will implement the interface, thus inverting the dependency.
I wonder, how is it applied in object-oriented languages with no interface? For example, I'm ... |
I am a beginning programmer who has written a spider application in PHP. Currently there are three parts:
1) The Spider (spider.php)
2) The Harvester (harvest.php)
3) The Configuration file (for example, craigslist_config.php)
I use the spider to search the web for items I want to buy. An item can be found on any webs... |
Programming question:
Reverse words in a string (words are separated by one or more spaces).
Now do it in-place.
What does "in-place" mean in the above context for an interpreted language like PHP or JavaScript?
|
I've seen many lists on the internet that includes many 'ities' (maintainability, scalability, portability, etc), but I'm not sure if animations, screen transitions, and similar features are functional or non functional requirements.
|
Suppose I'm building a JSON API and would like to include an endpoint that returns a list of recently created posts. Somewhere in my system is an existing Post model with the following test:
create a few posts in the db (some new, some old)
posts = Post.recent
assert that posts only contains new posts
Now I want to ... |
I am creating a web application in java where I need to mock the following flow.
When user trigger a certain process (add product to cart), I need to pass through following steps
Need to see in HTTP Session if user is logged in.
Check HTTP Session if shopping cart is there
If user exist in HTTP Session and his/her car... |
We are having a debate and I am struggling to decide which side to come down on. Basically we have an event type lets say like like this (simplified example).
public class Event
{
public virtual int EventId { get; set; }
public virtual DateTime DateTimeOccurred { get; set; }
}
Many different events in our sys... |
I was doing edit reviews on Stack Overflow and found out that people keeps correcting the word "boolean", replacing it with "Boolean" when it appears in text (but not in source code, of course). And then I found out that the spelling checker in my browser agrees with them.
Is there any rationale behind this? It seems g... |
I was having a discussion with a colleague and he bought up the topic of MVC and the use of ViewModels in ASP.NET MVC.
The discussion was that, in an n-layer architecture, the UI, Business Layer and Data Access Layer are individual assemblies/projects and ViewModels are the UI's representation of a database/business ob... |
Please tell me if:
Node.js will make our site faster!
Node.js will consume fewer server resources, we can save money!
Node.js will make us more productive!
Node.js means we can share client and server side JavaScript code.
To clarify, we're rewriting a frontend server, which will talk to our existing Ruby on Rails ap... |
I am conducting academic research on the topic of Extreme Programming and whether its practices lead to creating space for more errors and bugs in applications.
From the experiences I gathered from many, I have comments that fall on both sides. Many support it and consider it a daily necessity, with dynamics that can ... |
I am working in a windows service (using VB.Net) for internal use of my department. When ever a certain type of exception (FooException for now on) is captured, I follow the same logic:
Log the exception
Send an email to someone.
In order to reuse code and not to copy-paste the same lines in every catch FooException ... |
I have a large XML file (about 75,000 lines) where I have to build a catalogue (houses) from. Building the lists works fine, but now I have a problem.
The catalogue should have a detailed presentation page of one house. One house (<item id="123">) has about 800-1200 lines of data, based on the house type.
Which is the ... |
I am trying to explain the dependency inversion principle to my (mostly junior) colleagues. How can we define which one is the "high-level policy" and which one is the "low-level detail" in a software? For example, if our software automates workflow of several business applications, why do we say that the workflow auto... |
Hello fellow programmers!
I have a 2D graph which is best described as a Cartesian grid with traversible and non-traversible cells. I'd like to be able to detect subsets of this graph where the diffusion behaves anisotropically, i.e.: it is constrained by corridor-like passages.
I initially turned to diffusion tensor ... |
Leave a open database connection throughout the execution of the aplication, or for each time a operation will be executed a new connection will be created?
Open throughout the execution:
Open aplication -> Open connection;
Operations -> use the opened connection -> commit;
Close aplication -> close connection;
For ea... |
I'm pretty sure this is a question purely about aesthetics but I wanted to get all your opinions on it before I start proliferating this type of code in my codebase. Consider the following code:
//Foo.h
class Bar;
class Foo
{
public:
Bar& GetBar(){return *bar.get();}
private:
std::unique_ptr<Bar> ... |
I’ve had this gut feeling about Windows Workflow (WW) for a while now. And, until now, I couldn’t think of the right words to say in order to explain it. Since I think I have a good way to verbalize it now, I thought I’d share.
I believe there is a problem in our industry where a great percentage of developers take a l... |
Not being a Java practitioner, I recently came to learn about the JAX-RS specification and Apache CXF framework. While still wrapping my head around all these things, I also read the this question on SO.
Since MVC is a design pattern while JAX-RS is a specification, I was confused about the comparison. Granted my nasce... |
I work in a small web development company (3 programmers) for a while. During the last year the company had hard times (less projects) and a few co-workers were fired, including our Production Manager. Having this person out of our team mean to us that we have to deal more and more with the company bosses (owners). It'... |
I have been trying to wrap my head around MVC pattern for about 6 months.I've read tons of articles, Q&A, and blog posts about MVC and HMVC patterns, but I just simply don't get it 100%.
I tried learning MVC by exercising one of widely used PHP MVC framework, CodeIgniter. I've implemented few internal websites for my c... |
So there are 3 computers that I use to work on this project with, my home PC, work PC, and work Mac (for building to devices). The project has an SVN repository that two other programmers use so I can't commit broken code to it. The lead doesn't know how to use version control so the trunk contains art assets and every... |
I am dissatisfied with the file comparison tools I have worked with so far. While no tool would be able to always predict the line matchings that make best sense, at least current tools should be able to do a better job when changes mostly consist of added and removed indentation. But the tools have I used end up match... |
I'm working on a wishlist system, where users can add items to their various wishlists, and I plan to allow users to re-order the items later on. I am not really sure about the best way to go about storing this in a database while remaining fast and not turning in to a mess (this app will be used by a fairly large user... |
I am trying to understand this:
I wrote a code for points on a circle of radius 1. Note that the first and last point intentionally coincide.
do i=1,imax
X(i,1) = COS(-2*4.0*ATAN(1.0)*(i-1)/(imax-1))
Y(i,1) = SIN(-2*4.0*ATAN(1.0)*(i-1)/(imax-1))
print *, X(i,1)**2 + Y(i,1)**2
end do
The code is supposed to be a circ... |
I have successfully connected my microcontroller to my TV via through VGA adapter i made that convert digital to analog signals with the help of resistors.
Currently i am utilizing 8 pins that I am using as 2 Red 2 Green 2 Blue 1 Hsyn and 1 Vsyn. I was thinking if there is a way to add 'A' Alpha in it, it's used for t... |
I would like to convert this Java applet into an equivalent web app. This is my first time creating a web app, but I have some programming experience and time, and am willing to teach myself all of the necessary tools.
By "web app", I mean an application which would work in browsers without requiring Java or Flash, for... |
References and pointers do the same thing as I know. Is there any difference between them?
If there is no difference, why we call them reference not pointer?
|
In an MVP application, what should be the most appropriate way to implement restriction to some UI actions based on the current user's privileges?
For example, in a role-based security, different roles will have different access to some UI interactions on the same view. If, for instance, we have an online store, on the... |
The general recommendation to record original scanned images used to be "use TIFF". But programmers need evolution of format for "evolution of software", and I need to evolve my system to change from TIFF to JP2.
I have a big image storage (terabytes) for legal and scientific scanned materials, they need original reco... |
I have a long time running project. Its been running for about 6 months. The project is very big. The lead developer/team leader designed the project and the whole project is in his brain. He knows all ins and outs. I also know almost everything. But I am not confident like him.
Problem is recently he is charging qui... |
I've been writing most of my javascript applications in an OO style close to what I would use for most other languages. However, this means that most callbacks need to have a reference to an object, and I generally handle that by using $.proxy (or dojo.hitch, or whatever the framework's tool for this is) to be sure tha... |
My cousin (Age 10) who studies in Standard 5. He wants to learn programming and programming logic.
Which book or resources should I refer? Is there any Good Data Structure book to improve programming logic specially for children?
|
I've been working on improving an existing library to be more maintainable after trying to implement a feature I wanted and found the code to be hard to alter.
The library is a node.js grunt plugin called grunt-contrib-jshint and my implementation is in a repo called grunt-jshint-bfs.
I've run a code analysis tool call... |
I am trying to understand how stack frames are built and which variables (params) are pushed to stack in what order? Some search results showed that the C/C++ compiler decides based on operations performed within a function. For example, if the function was supposed to just increment a passed-in int value by 1 (simila... |
Originally, this is a part of another question.
Why is sizeof called a compile-time operator? Isn't it actually a run-time operator? And if it is indeed a compile-time operator, how does it help in producing portable code which runs the same in different computers ? Please explain in detail.
|
We have lots of user-generated images on our site. When users upload their images, we only store the original. However, depending on the page, we show different sizes of those images (small, medium, large, original). Is it necessary to store all sizes of these images or is there a better way? Currently, we are resi... |
For performance issue I want the logging send to a new thread.
While the main program can work, the new thread can write the error or other messages to a file without effect to the main program. How could I send all stdout to the new thread?
Work to be done:
create a new thread, ok
open a file, ok
create a pipe inside... |
What is a XML schema in plain simple terms? What will be the problem if an XML doesn't have a schema defined? An example can be very helpful.
|
Can we create a program that print out its source code what if we (or the program itself) compile than the new program would have the same exact functionality what the original program has? So somehow it would reproduce himself in perfect clones that can reproduce too.
The program shouldn't use any external files other... |
I'm a member of a small new team and with one of our latest builds I noted that, VS2010 code files don't contain language formatting.
So for example when I write down a Euro symbol in my code or use a "." or "," in numbers or use Pounds, Euro or Dollar symbols, those look ok in my code, but for a coder in Russia th... |
In C# what is the best practice for encapsulating variables I need to use in multiple methods? Is it OK to simply declare them at the top of my class above the two methods?
Also if I am using app settings from my config file should I use a getter? like this...
private string mySetting{ get { return WebConfigurationMan... |
In database managements systems lecture, my professor said that we can use Oracle etc. ui designing tools instead of using Visual C# or etc. He added that SQL is as strong as a programming language. So I wonder why do we still use these programming languages for desktop applications which mostly adds/deletes/updates re... |
For example to read data from a website we do:
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
The method that executes the HTTP request, returns a response, then we turn the response into an entity, then we turn ... |
I notice that a property of codebases that I like hacking on is that it's quick to find the relevant code for some feature, without knowing much about the code base at all. For example, searching for a label in the GUI, and immediately hitting the code that implements that feature.
This seems to be in direct tension wi... |
here's the link of the app:
https://play.google.com/store/apps/details?id=com.iatll.airlock
I had studied AI in the final year of b.tech cs programme, and i do remember some algorithm of generating and solving the 8 puzzle game; we had to implement it in Prolog (tough times)
But I'm not sure if the above mentioned a... |
I have predicate, that enumerates through backtracking list of values. I want to find highest value from this list.
For example:
ranked_move(X,Y,R) :- between(0,10,Y), between(0,10,X), rank_move(X,Y,R).
top_move(X,Y) :- % X, Y for highest R
Right now, I have it solved by using findall and custom predicate that goes th... |
I have been thinking about it and wanted some feedback, recently I thought about doing it like this:
function foo(){
if ( !foo.prototype.statics ){
foo.prototype.statics = {
// declare static functions/vars here
}
}
if ( !(this instanceof foo) ){
return foo.prototype.statics;
... |
I have written a rather small App with only one activity. From my understanding an activity has to be seen as kind of a view and controller in one class.
But even for a little app, with 3 dialogs (made with AlertDialogBuilder and all those anonymous inner classes that come with it) my activity has 500+ LOC and became v... |
I am thinking about starting a small project and I want to make its versioning with git.
Bitbucket seems a good option for me with their free plan. I want to use it as the main tool for working with git since they have nice tools like a web-interface, Mac OS client, and so on. But, in order to have higher protection f... |
Let's say I have BaseA and BaseB classes. BaseB can have to several references of BaseA instances. Now, we have two other classes, DerivedA and DerivedB that respectively inherit from BaseA and BaseB.
How can I show in such a diagram that DerivedB should only store instances of DerivedA and not instances of BaseA? It ... |
As the title says, if the user wants change their email address in the application, in terms of programming, what approach (process) to use? Where do you store the new email address until the user will confirms it?
|
I'm reading about SOA and the four tenets required to make a SOA application. I have tried different sources, but the explanations are twisting. I'm searching for something that is a bit less abstract. Is my interpretation correct?
The four tenets is:
Services have explicit boundaries
Services are autonomous
Services ... |
Let's say we have an abstract class and let this class has only abstract methods. Is this abstract class different from an interface that has same methods only?
What I am looking to know is if there are any differences both philosophically, objectively and in the underlying programming language implementation between a... |
Working on my own I tought I need to learn that css3 shorthand properties, because - as I know now, it affects website's loading time, so I need to optimize it a little bit.
I was thinking - is there any order how to write property values, when using shorthand prop's?
For example: font: 1em/1.5em bold italic serif
|
I have a database that contains projects and each project contains many samples. I want a project level threshold value, to trigger highlighting when a field on the sample is above this threshold. I also want to be able to override the threshold at the individual sample level.
So I can see two ways to implement this: ... |
I have an internal database at my work. At the moment we are using excel to import data, but this is very error prone, so I would like to replace this with some javascript based application which exposes some of the data in lookup tables in dropdown menus, for our customers to fill in, on a public website.
So my intern... |
I put up a webpage advertising a particular birthday party. A simple html page served by apache2 on ubuntu server 12.04. I have a link on the page to a cgi script-Python-that asks the requester to submit text values that will be formatted and relayed in an email to the bithrday boy. What's a simple way to authenticate ... |
The questions says it all, but a quick overview of the situation. I'm creating a Model which contains classes (all inherriting myObject) which have a large amount of interconnection. I want the controller to be able to create any of these objects any time, without modifying the Model. Only an explicit cal to the mod... |
So my company is using TFS and SQL to Manage their Database (MS SQL Server). It integrates with the nightly build servers to do builds and produce scripts to build the entire Database. Also the Compare Schema tool that visual studio offers is really handy.
We want to do the same with Oracle, Preferably with TFS if that... |
How should we load balance listeners to a 3rd party service?
e.g. We need to read gtalk messages via XMPP Listener and build an application using the interactions of the user with a chatbot. In such a case, how would we ensure that we can have XMPP listeners on multiple servers and we load balance the messages between ... |
Is there a difference between HttpRequest and xmlHttpRequest in terms of security? Is one more secure than the other?
Is it more secure to send important data such as passwords via HttpRequest than via xmlHttpRequest ?
Is data packing in both done the same way?
|
Is it good to use nested classes or should I use namespaces instead?
In context:
I have a templated codec loader and a codec have In objects and Out objects
template<class TypeOfData>
class Codec
{
private:
typename TypeOfData::In* reader;
typename TypeOfData::Out* writer;
};
On the other h... |
In a recent interview I asked the interviewers "how do you go about evaluating new technologies and libraries (such as SignalR) and bringing them in to use?". They said they don't, that instead they write everything themselves so they don't have to rely on anyone else.
The firm doesn't work for the government or defenc... |
In Software Engineering Methodologies... The Evolutionary Development contains Exploratory & Prototyping...
Is Exploratory Development same as Incremental Development... What do you mean by exploratory Development?
The terms are taken from
Software Engineering - Ian Sommerville
|
Been brushing up on my C++ lately, on Ubuntu QQ. I love the Qt framework for everything, especially building GUI's. I became quite familiar with it when using PyQt over the last few years.
When using PyQt, I had some issues that are now more pronounced when using C++ with Qt: Qt has many extensions to C++ that are Qt ... |
I'm looking into developing my entities so that they cannot be in an invalid state.
In particular I'm starting with my Customer entity. This would have fields like:
Title (enum)
FirstName (string)
LastName (string)
Address (value object with another 6 fields)
MainTelephone (string)
AlternateTelephone (string)
EmailAd... |
I am talking about 20-30+ millions lines of code, software at the scale and complexity of Autodesk Maya for example.
If you freeze the development as long as it needs to be, can you actually fix all the bugs until there is simply not a single bug, if such a thing could be verified by computers? What are the arguments f... |
Does anyone know how to create an algorithm capable of making the figure just like in the picture, when given a set of specific points (3D array)
|
I'm trying to include a feature on my website that verifies retail gift card balances on cards previously registered at the retailer's website by the card holder. Can this simply be done by writing an algorithm that pulls and aggregates this data on my site?
|
Sometimes I hesitate between "More code to avoid unnecessary operations" and "less code but with redundant operations". Let me just take an example (Win32 API):
I try to paint some controls manually when the cursor is over it. If the cursor is over this control and it is painted, then it doesn't need to be painted agai... |
I have read that equivalence partitioning can be used typically for intervals or lists, e.g. I assume it can be used for every set of inputs.
Anyway if the requirement says that allowed colors are (RED,BLUE,BLACK, GREEN), I cannot treat them like a list, right? I mean, testing one of them would not be enough because de... |
Is it bad that I often find myself spending more time on program structure than actually writing code inside methods? Is this common?
I feel I spend more time laying the foundation than actually building the house (metaphorically). While I understand that without a good foundation the house will cave in, but does it le... |
I'm working in an organisation with limited funds. They can't afford a business account on Dropbox. However, they would find it useful to have all their files synchronized on local machines.
I've recently looked at Python Sockets and it looks as though a custom script could achieve what they're looking for. I'm concer... |
The values of a function of two variables z = f (x, y), where x, y, z take integer values are stored in sql db. Calculate (appoint) the largest surface area of the flat. By 'flat area' we mean an area about which for each pair of x and y lying inside the area about the value of the function is constant (z = const).... |
I am in charge of a project on github that has files that are and are not code based. Specifically, I am worried about our SolidWorks files. How do I ensure these files are covered by the GPLv3 license?
|
I am working on an application, a module of which does the following financial operations sequentially:
When a user requests for a certain amount to be transferred into her bank account:
check whether any transaction can happen now? (transaction can be carried out only during a certain time period)
check whether the u... |
It seems that NoSQL concept not something very new and innovative, but these days become very popular. Why it become popular recently but not happen in the time when SQL is very popular?
|
I am learning how to draw a UML class diagram and after reading a few tutorials, I am still confused about the appropriate usages of Association type (The clear diamond and black diamond). I understand their usages but I haven't got a very concrete understanding on when to use them and when not to.
For example in the ... |
Let me explain my situation. I'm planning a kind of test case runner for doing testcases on external devices, which are microcontroller based. Lets consider the devices:
Device 1
Device 2
There exist a lot of test cases which can be run with one of the devices above. For example:
Testcase 1
Testcase 2
The main reas... |
I'm a self-taught intermediate Python programmer; I frequently come across popular books on software development and programming written in other languages (often Java).
Typical examples:
Refactoring: Improving the Design of Existing Code
Design Patterns, Gang of Four
Test Driven Development: By Example
The Art of Un... |
As part of a ray tracer implementation, I need to compute the barycentric coordinates in a triangle in 3D in order to decide if a ray hits the triangle or not. In theory this could be done by simply solving a few linear equations. But due to the fact that the vertices of a triangle could have the same x, y or z coordin... |
I assume that negative testing is an approach to design the test cases and so is equivalence partitioning. But I am not sure if NT is a part of ET.
An example:
A field can accept a numeric value from the range 0-10.
So I have three partitions: to 0, from 0-10 and more than 10.
Another invalid partitions would represent... |
I was reading some Cthulhu Mythos stuff and started to think about those various signs and symbols that are used in the texts. Of course those are made by humans but point is that they look natural to human eyes.
So, what kind of algorithm would be needed to create natural looking symbols and signs? How this problem c... |
Many PHP web applications follow this model for installation and upgrade:
Un-tar a source tar ball.
Point Apache at the source.
Navigate a web browser to the home page.
Go through several web pages of set-up (e.g., checks for existence of libraries, asks for database connection information, creates or updates database... |
I need some opinion. GCC was always a very good compiler, but recently it is losing "appeal".
I have just found that on Windows GCC does not have std::thread support, forcing Windows users to use another compiler because the most exciting feature is still missing.
But why really doesn't GCC still have threads support u... |
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