Search Results

Search found 3518 results on 141 pages for 'arguments'.

Page 72/141 | < Previous Page | 68 69 70 71 72 73 74 75 76 77 78 79  | Next Page >

• RPi and Java Embedded GPIO: Java code to blink more LEDs

  - by hinkmond

  Now, it's time to blink the other GPIO ports with the other LEDs connected to them. This is easy using Java Embedded, since the Java programming language is powerful and flexible. Embedded developers are not used to this, since the C programming language is more popular but less easy to develop in. We just need to use a dynamic Java String array to map to the pinouts of the GPIO port names from the previous diagram posted. This way we can address each "channel" with an index into that String array. static String[] GpioChannels = { "0", "1", "4", "17", "21", "22", "10", "9" }; With this new dynamic array, we can streamline the main() of this Java program to activate all the ports. /** * @param args the command line arguments */ public static void main(String[] args) { FileWriter[] commandChannels; try { /*** Init GPIO port for output ***/ // Open file handles to GPIO port unexport and export controls FileWriter unexportFile = new FileWriter("/sys/class/gpio/unexport"); FileWriter exportFile = new FileWriter("/sys/class/gpio/export"); for (String gpioChannel : GpioChannels) { System.out.println(gpioChannel); // Reset the port unexportFile.write(gpioChannel); unexportFile.flush(); // Set the port for use exportFile.write(gpioChannel); exportFile.flush(); // Open file handle to port input/output control FileWriter directionFile = new FileWriter("/sys/class/gpio/gpio" + gpioChannel + "/direction"); // Set port for output directionFile.write(GPIO_OUT); directionFile.flush(); } And, then simply add array code to where we blink the LED to make it blink all the LEDS on and off at once. /*** Send commands to GPIO port ***/ commandChannels = new FileWriter[GpioChannels.length]; for (int channum=0; channum It's easier than falling off a log... or at least easier than C programming. Hinkmond

  Read the article

• Sucking Less Every Year?

  - by AdityaGameProgrammer

  Sucking Less Every Year -Jeff Atwood I had come across this insightful article.Quoting directly from the post I've often thought that sucking less every year is how humble programmers improve. You should be unhappy with code you wrote a year ago. If you aren't, that means either A) you haven't learned anything in a year, B) your code can't be improved, or C) you never revisit old code. All of these are the kiss of death for software developers. How often does this happen or not happen to you? How long before you see an actual improvement in your coding ? month, year? Do you ever revisit Your old code? How often does your old code plague you? or how often do you have to deal with your technical debt. It is definitely very painful to fix old bugs n dirty code that we may have done to quickly meet a deadline and those quick fixes ,some cases we may have to rewrite most of the application/code. No arguments about that. Some of the developers i had come across argued that they were already at the evolved stage where their coding doesn't need improvement or cant get improved anymore. Does this happen? If so how many years into coding on a particular language does one expect this to happen? Related: Ever look back at some of your old code and grimace in pain? Star Wars Moment in Code "Luke! I am your code!" "No! Impossible! It can't be!"

  Read the article

• Tender vs. Requirements vs. Solution Design

  - by Tom Tom

  Conventionally, which of the above documents is deemed to hold the most weight when it comes to system acceptance? I recently had a conversation along these lines: It was argued that the initial requirements / tender documentation should be used to determine system acceptance. It was said that the solution design only serves to describe the way in which the system will solve the problem, not the problem it will solve. Furthermore, it was argued that if requirements are missed during solution design, the requirements should be referenced during system acceptance and that if any requirements were missed then the original tender should be referenced. Conversely, I suggested that - while requirements may be based on the original tender - they supersede it once agreed with the stakeholders. Furthermore, during solution design, analysis is performed to address and refine these initial requirements, translating them into a system capable of meeting the actual requirements. Once signed off by the relevant users, this solution design should absolutely represent the requirements (by virtue of the fact that it's designed upon them) but actually supersedes them as the basis for system acceptance. Is one of the above arguments more valid than the other?

  Read the article

• Performing client-side OAuth authorized Twitter API calls versus server side, how much of a difference is there in terms of performance?

  - by Terence Ponce

  I'm working on a Twitter application in Ruby on Rails. One of the biggest arguments that I have with other people on the project is the method of calling the Twitter API. Before, everything was done on the server: OAuth login, updating the user's Twitter data, and retrieving tweets. Retrieving tweets was the heaviest thing to do since we don't store the tweets in our database, so viewing the tweets means that we have to call the API every time. One of the people in the project suggested that we call the tweets through Javascript instead to lessen the load on the server. We used GET search, which, correct me if I'm wrong, will be removed when v1.0 becomes completely deprecated, but that really isn't a concern now. When the Twitter API has migrated completely to v1.1 (again, correct me if I'm wrong), every calls to the API must be authenticated, so we have to authenticate our Javascript requests to the API. As said here: We don't support or recommend performing OAuth directly through Javascript -- it's insecure and puts your application at risk. The only acceptable way to perform it is if you kept all keys and secrets server-side, computed the OAuth signatures and parameters server side, then issued the request client-side from the server-generated OAuth values. If we do exactly what Twitter suggests, the only difference between this and doing everything server-side is that our server won't have to contact the Twitter API anymore every time the user wants to view tweets. Here's how I would picture what's happening every time the user makes a request: If we do it through Javascript, it would be harder on my part because I would have to create the signatures manually for every request, but I will gladly do it if the boost in performance is worth all the trouble. Doing it through Ruby on Rails would be very easy since the Twitter gem does most of the grunt work already, so I'm really encouraging the other people in the project to agree with me. Is the difference in performance trivial or is it significant enough to switch to Javascript?

  Read the article

• Misconceptions about purely functional languages?

  - by Giorgio

  I often encounter the following statements / arguments: Pure functional programming languages do not allow side effects (and are therefore of little use in practice because any useful program does have side effects, e.g. when it interacts with the external world). Pure functional programming languages do not allow to write a program that maintains state (which makes programming very awkward because in many application you do need state). I am not an expert in functional languages but here is what I have understood about these topics until now. Regarding point 1, you can interact with the environment in purely functional languages but you have to explicitly mark the code (functions) that introduces them (e.g. in Haskell by means of monadic types). Also, AFAIK computing by side effects (destructively updating data) should also be possible (using monadic types?) but is not the preferred way of working. Regarding point 2, AFAIK you can represent state by threading values through several computation steps (in Haskell, again, using monadic types) but I have no practical experience doing this and my understanding is rather vague. So, are the two statements above correct in any sense or are they just misconceptions about purely functional languages? If they are misconceptions, how did they come about? Could you write a (possibly small) code snippet illustrating the Haskell idiomatic way to (1) implement side effects and (2) implement a computation with state?

  Read the article

• How to visualize the design of a program in order to communicate it to others

  - by Joris Meys

  I am (re-)designing some packages for R, and I am currently working out the necessary functions, objects, both internal and for the interface with the user. I have documented the individual functions and objects. So I have the description of all the little parts. Now I need to give an overview of how the parts fit together. The scheme of the motor so to say. I've started with making some flowchart-like graphs in Visio, but that quickly became a clumsy and useless collection of boxes, arrrows and-what-not. So hence the question: Is there specific software you can use for vizualizing the design of your program If so, care to share some tips on how to do this most efficiently If not, how do other designers create the scheme of their programs and communicate that to others? Edit: I am NOT asking how to explain complex processes to somebody, nor asking how to illustrate programming logic. I am asking how to communicate the design of a program/package, i.e.: the objects (with key features and representation if possible) the related functions (with arguments and function if possible) the interrelation between the functions at the interface and the internal functions (I'm talking about an extension package for a scripting language, keep that in mind) So something like this : But better. This is (part of) the interrelations between functions in the old package that I'm now redesigning for obvious reasons :-) PS : I made that graph myself, using code extraction tools on the source and feeding the interrelation matrix to yEd Graph Editor.

  Read the article

• Inheritance vs composition in this example

  - by Gerenuk

  I'm wondering about the differences between inheritance and composition examined with concrete code relevant arguments. In particular my example was Inheritance: class Do: def do(self): self.doA() self.doB() def doA(self): pass def doB(self): pass class MyDo(Do): def doA(self): print("A") def doB(self): print("B") x=MyDo() vs Composition: class Do: def __init__(self, a, b): self.a=a self.b=b def do(self): self.a.do() self.b.do() x=Do(DoA(), DoB()) (Note for composition I'm missing code so it's not actually shorter) Can you name particular advantages of one or the other? I'm think of: composition is useful if you plan to reuse DoA() in another context inheritance seems easier; no additional references/variables/initialization method doA can access internal variable (be it a good or bad thing :) ) inheritance groups logic A and B together; even though you could equally introduce a grouped delegate object inheritance provides a preset class for the users; with composition you'd have to encapsule the initialization in a factory so that the user does have to assemble the logic and the skeleton ... Basically I'd like to examine the implications of inheritance vs composition. I heard often composition is prefered, but I'd like to understand that by example. Of course I can always start with one and refactor later to the other.

  Read the article

• I don't understand the definition of side effects

  - by Chris Okyen

  I don't understand the wikipedia article on Side Effects: In computer science, a function or expression is said to have a side effect if, in addition to returning a value, it also 1.) Modifies some state or 2.) Has an observable interaction with calling functions or the outside world. I know an example of the first thing that causes a function or expression to have side effects - modifying a state Function and Expression modifying a state : 1.) foo(int X) { return x = x % x; } a = a + 1; What does 2.) - Has an observable interaction with calling functions or the outside world," mean? - Please give an example. The article continues on to say, "For example, a function might modify a global or static variable, modify one of its arguments, raise an exception, write data to a display or file, read data, or call other side-effecting functions...." Are all these examples, examples of 1.) - Modifiying some state , or are they also part of 2.) - Has an observable interaction with calling functions or the outside world?

  Read the article

• Happy Tau Day! (Or: How Some Mathematicians Think We Should Retire Pi) [Video]

  - by Jason Fitzpatrick

  When you were in school you learned all about Pi and its relationship to circles and turn-based geometry. Some mathematicians are rallying for a new lesson, on about Tau. Michael Hartl is a mathematician on a mission, a mission to get people away from using Pi and to start using Tau. His manifesto opens: Welcome to The Tau Manifesto. This manifesto is dedicated to one of the most important numbers in mathematics, perhaps the most important: the circle constant relating the circumference of a circle to its linear dimension. For millennia, the circle has been considered the most perfect of shapes, and the circle constant captures the geometry of the circle in a single number. Of course, the traditional choice of circle constant is p—but, as mathematician Bob Palais notes in his delightful article “p Is Wrong!”,1 p is wrong. It’s time to set things right. Why is Pi wrong? Among the arguments is that Tau is the ration of a circumference to the radius of a circle and defining circles by their radius is more natural and that Pi is a 2-factor number but with Tau everything is based of a single unit–three quarters of a turn around a Tau-defined circle is simply three quarters of a Tau radian. Watch the video above to see the Tau sequence (which begins 6.2831853071…) turned into a musical composition. For more information about Tau hit up the link below to read the manifesto. The Tau Manifesto [TauDay] HTG Explains: Photography with Film-Based CamerasHow to Clean Your Dirty Smartphone (Without Breaking Something)What is a Histogram, and How Can I Use it to Improve My Photos?

  Read the article

• Empty interface to combine multiple interfaces

  - by user1109519

  Suppose you have two interfaces: interface Readable { public void read(); } interface Writable { public void write(); } In some cases the implementing objects can only support one of these but in a lot of cases the implementations will support both interfaces. The people who use the interfaces will have to do something like: // can't write to it without explicit casting Readable myObject = new MyObject(); // can't read from it without explicit casting Writable myObject = new MyObject(); // tight coupling to actual implementation MyObject myObject = new MyObject(); None of these options is terribly convenient, even more so when considering that you want this as a method parameter. One solution would be to declare a wrapping interface: interface TheWholeShabam extends Readable, Writable {} But this has one specific problem: all implementations that support both Readable and Writable have to implement TheWholeShabam if they want to be compatible with people using the interface. Even though it offers nothing apart from the guaranteed presence of both interfaces. Is there a clean solution to this problem or should I go for the wrapper interface? UPDATE It is in fact often necessary to have an object that is both readable and writable so simply seperating the concerns in the arguments is not always a clean solution. UPDATE2 (extracted as answer so it's easier to comment on) UPDATE3 Please beware that the primary usecase for this is not streams (although they too must be supported). Streams make a very specific distinction between input and output and there is a clear separation of responsibilities. Rather, think of something like a bytebuffer where you need one object you can write to and read from, one object that has a very specific state attached to it. These objects exist because they are very useful for some things like asynchronous I/O, encodings,...

  Read the article

• Why is Desktop Unity using the global application menu?

  - by Kazade

  It was announced in another question that the desktop version of Unity will keep the global menu by default. Here are the facts: The global menu was introduced into UNE to save vertical screen space because at Netbook resolutions the vertical space is limited. On a modern desktop with a high resolution, there is ample vertical space making this unnecessary On the announcement of UNE global menus, Mark Shuttleworth himself said the following: "There are outstanding questions about the usability of a panel-hosted menu on much larger screens, where the window and the menu could be very far apart." The benefits of a global menu don't seem to carry across to a high-resolution desktop and instead seem to bring draw backs (increased mouse travel, large distance between the menu and its associated window). The other worrying factor is that applications seem to be moving away from having a menu bar, and instead of innovating on this and defining new guidelines for moving away from the menu, we are giving it prime place right at the top of the desktop. If applications continue moving away from the desktop we will have an inconsistent experience concerning where to locate application related options/tools depending on which app you are using (e.g. Chrome). Finally, the current global menu bar implementation doesn't work for all apps, and doesn't even work for all apps in the default install. This means that the default desktop implementation will be inconsistent. So, there are a bunch of reasons why moving to a global menu is a bad idea, so we need some pretty convincing arguments for why it is a good idea. What are the reasons for the global menu implementation in the desktop version of Unity?

  Read the article

• How to create a copy of an instance without having access to private variables

  - by Jamie

  Im having a bit of a problem. Let me show you the code first: public class Direction { private CircularList xSpeed, zSpeed; private int[] dirSquare = {-1, 0, 1, 0}; public Direction(int xSpeed, int zSpeed){ this.xSpeed = new CircularList(dirSquare, xSpeed); this.zSpeed = new CircularList(dirSquare, zSpeed); } public Direction(Point dirs){ this(dirs.x, dirs.y); } public void shiftLeft(){ xSpeed.shiftLeft(); zSpeed.shiftRight(); } public void shiftRight(){ xSpeed.shiftRight(); zSpeed.shiftLeft(); } public int getXSpeed(){ return this.xSpeed.currentValue(); } public int getZSpeed(){ return this.zSpeed.currentValue(); } } Now lets say i have an instance of Direction: Direction dir = new Direction(0, 0); As you can see in the code of Direction, the arguments fed to the constructor, are passed directly to some other class. One cannot be sure if they stay the same because methods shiftRight() and shiftLeft could have been called, which changes thos numbers. My question is, how do i create a completely new instance of Direction, that is basically copy(not by reference) of dir? The only way i see it, is to create public methods in both CircularList(i can post the code of this class, but its not relevant) and Direction that return the variables needed to create a copy of the instance, but this solution seems really dirty since those numbers are not supposed to be touched after beeing fed to the constructor, and therefore they are private.

  Read the article

• Object oriented wrapper around a dll

  - by Tom Davies

  So, I'm writing a C# managed wrapper around a native dll. The dll contains several hundred functions. In most cases, the first argument to each function is an opaque handle to a type internal to the dll. So, an obvious starting point for defining some classes in the wrapper would be to define classes corresponding to each of these opaque types, with each instance holding and managing the opaque handle (passed to its constructor) Things are a little awkward when dealing with callbacks from the dll. Naturally, the callback handlers in my wrapper have to be static, but the callbacks arguments invariable contain an opaque handle. In order to get from the static callback back to an object instance, I've created a static dictionary in each class, associating handles with class instances. In the constructor of each class, an entry is put into the dictionary, and this entry is then removed in the Destructors. When I receive a callback, I can then consult the dictionary to retrieve the class instance corresponding to the opaque reference. Are there any obvious flaws to this? Something that seems to be a problem is that the existence static dictionary means that the garbage collector will not act on my class instances that are otherwise unreachable. As they are never garbage collected, they never get removed from the dictionary, so the dictionary grows. It seems I might have to manually dispose of my objects, which is something absolutely would like to avoid. Can anyone suggest a good design that allows me to avoid having to do this?

  Read the article

• Seeking for a better solution to restrict access in GRUB2 menu

  - by LiveWireBT

  I just read that in certain situations you should also protect access to your GRUB2 menu by setting a password and may be refining acces by adding --unrestricted or --users as arguments to menuentries und submenus. I read the corresponding pages in the Ubuntu Community Documentation and the Arch Wiki. So, I created /etc/grub.d/01_security, stored usernames and passwords in there, made the file executable and ran update-grub. This is working as intended, every action in the menu prompts for username and password, but I also want to modify the automatically generated entries to either restrict them to certain users (via --users) or make them available for everyone, but not editable by everyone (via --unrestricted). I was able to find the proper lines in 10_linux and edit them accordingly, however I'd love to see an easier solution. Perhaps an option like GRUB_DISABLE_RECOVERY="true" or GRUB_DISABLE_OS_PROBER=true in /etc/default/grub for easy (re)configuration (for linux and os-prober generated entries). Here's a diff from my 13.10 installation: $ diff /etc/grub.d/10_linux /etc/grub.d/10_linux_bak 123c123 < echo "menuentry '$(echo "$title" | grub_quote)' ${CLASS} --unrestriced \$menuentry_id_option 'gnulinux-$version-$type-$boot_device_id' {" | sed "s/^$ --- > echo "menuentry '$(echo "$title" | grub_quote)' ${CLASS} \$menuentry_id_option 'gnulinux-$version-$type-$boot_device_id' {" | sed "s/^/$submenu_inde$ 125c125 < echo "menuentry '$(echo "$os" | grub_quote)' ${CLASS} --unrestricted \$menuentry_id_option 'gnulinux-simple-$boot_device_id' {" | sed "s/^/$submenu_$ --- > echo "menuentry '$(echo "$os" | grub_quote)' ${CLASS} \$menuentry_id_option 'gnulinux-simple-$boot_device_id' {" | sed "s/^/$submenu_indentation/" 323c323 < echo "submenu --unrestricted '$(gettext_printf "Advanced options for %s" "${OS}" | grub_quote)' \$menuentry_id_option 'gnulinux-advanced-$boot_device_$ --- > echo "submenu '$(gettext_printf "Advanced options for %s" "${OS}" | grub_quote)' \$menuentry_id_option 'gnulinux-advanced-$boot_device_id' {" tl;dr: I'd love the see a simple solution for GRUB2 entries that cannot be modified without a password or are limited to certain users. (Yes, GRUB_DISABLE_RECOVERY="true" is active.)

  Read the article

• In MVC , DAO should be called from Controller or Model

  - by tito

  I have seen various arguments against the DAO being called from the Controller class directly and also the DAO from the Model class.Infact I personally feel that if we are following the MVC pattern , the controller should not coupled with the DAO , but the Model class should invoke the DAO from within and controller should invoke the model class.Why because , we can decouple the model class apart from a webapplication and expose the functionalities for various ways like for a REST service to use our model class. If we write the DAO invocation in the controller , it would not be possible for a REST service to reuse the functionality right ? I have summarized both the approaches below. Approach #1 public class CustomerController extends HttpServlet { proctected void doPost(....) { Customer customer = new Customer("xxxxx","23",1); new CustomerDAO().save(customer); } } Approach #2 public class CustomerController extends HttpServlet { proctected void doPost(....) { Customer customer = new Customer("xxxxx","23",1); customer.save(customer); } } public class Customer { ........... private void save(Customer customer){ new CustomerDAO().save(customer); } } Note- Here is what a definition of Model is : Model: The model manages the behavior and data of the application domain, responds to requests for information about its state (usually from the view), and responds to instructions to change state (usually from the controller). In event-driven systems, the model notifies observers (usually views) when the information changes so that they can react. I would need an expert opinion on this because I find many using #1 or #2 , So which one is it ?

  Read the article

• Sucking Less Every Year ?

  - by AdityaGameProgrammer

  Sucking Less Every Year A trail of thought that had been on my mind for a while Quoting directly from the post I've often thought that sucking less every year is how humble programmers improve. You should be unhappy with code you wrote a year ago. If you aren't, that means either A) you haven't learned anything in a year, B) your code can't be improved, or C) you never revisit old code. All of these are the kiss of death for software developers. How often does this happen or not happen to you? How long before you see an actual improvement in your coding ? month, year? Do you ever revisit Your old code? How often does your old code plague you? or how often do you have to deal with your technical debt. It is definitely very painful to fix old bugs n dirty code that we may have done to quickly meet a deadline and those quick fixes ,some cases we may have to rewrite most of the application/code. No arguments about that. Some of the developers i had come across argued that they were already at the evolved stage where their coding doesn't need improvement or cant get improved anymore. Does this happen? If so how many years into coding on a particular language does one expect this to happen?

  Read the article

• How to Deal with an out of touch "Project manager"

  - by Joe

  This "manager" is 70+ yrs old and a math genius. We were tasked with creating a web application. He loves SQL and stored procedures. He first created this in MS access. For the web app I had to take his DB migrate to SQL server. His first thought was to have a master stored procedure with a WAITFOR Handling requests from users. I eventually talked him out of that and use asp.net mvc. Then eventually use the asp.net membership. Now the web app is a mostly handles requests from the pages that is passed to stored procedures. It is all stored procedure driven. The business logic as well. Now we are having an one open DB connection per user logged in plus 1. I use linq to sql to check 2 tables and return the values thats it period. So 25 users is a load. He complains why my code is bad cause his test driver stored procedure simulates over 100 users with no issue. What are the best arguments for not having the business logic not all in stored procedures?? How should I deal with this?? I am giving an abbreviated story of course. He is a genius part owner of the company all the other owners trust him because he is a genius. and quoting -"He gets things done. old school".

  Read the article

• How bad it's have two methods with the same name but differents signatures in two classes?

  - by Super User

  I have a design problem relationated with the public interface, the names of methods and the understanding of my API and my code. I have two classes like this: class A: ... function collision(self): .... ... class B: .... function _collision(self, another_object, l, r, t, b): .... The first class have one public method named collision and the second have one private method called _collision. The two methods differs in arguments type and number. In the API _m method is private. For the example let's say that the _collision method checks if the object is colliding with another_ object with certain conditions l, r, t, b (for example, collide the left side, the right side, etc) and returns true or false according to the case. The collision method, on the other hand, resolves all the collisions of the object with other objects. The two methods have the same name because I think is better avoid overload the design with different names for methods who do almost the same think, but in distinct contexts and classes. This is clear enough to the reader or I should change the method's name?

  Read the article

• for an ajax heavy web application which would be better SOAP or REST?

  - by coder

  I'm building an ajax heavy application (client-side strictly html/css/js) which will be getting all the data and using server business logic via webservices. I know REST seems to be the hot topic but I can't find any good arguments. The main argument seems to be its "light-weight". My impression so far is that wsdl/soap based services are more expressive and allow for more a more complex transfer of data. It appears that soap would be more useful in the application I'm building where the only code consuming the services will be the js downloaded in the client browser. REST on the other hand seems to have a smaller entry barrier and so can be more useful for services like twitter in allowing other developers to consume these services easily. Also, REST seems to Te better suited for simple data transfers. So in summary SOAP is useful for complex data transfer and REST is useful in simple data transfer. I'm currently under the impression that using SOAP would be best due to the complexity of the messages but perhaps there's other factors. What are your thoughts on the pros/cons of soap/rest for a heavy ajax web app?

  Read the article

• Should you always pass the bare minimum data needed into a function

  - by Anders Holmström

  Let's say I have a function IsAdmin that checks whether a user is an admin. Let's also say that the admin checking is done by matching user id, name and password against some sort of rule (not important). In my head there are then two possible function signatures for this: public bool IsAdmin(User user); public bool IsAdmin(int id, string name, string password); I most often go for the second type of signature, thinking that: The function signature gives the reader a lot more info The logic contained inside the function doesn't have to know about the User class It usually results in slightly less code inside the function However I sometimes question this approach, and also realize that at some point it would become unwieldy. If for example a function would map between ten different object fields into a resulting bool I would obviously send in the entire object. But apart from a stark example like that I can't see a reason to pass in the actual object. I would appreciate any arguments for either style, as well as any general observations you might offer. I program in both object oriented and functional styles, so the question should be seen as regarding any and all idioms.

  Read the article

• Understanding Application binary interface (ABI)

  - by Tim

  I am trying to understand the concept of Application binary interface (ABI). From The Linux Kernel Primer: An ABI is a set of conventions that allows a linker to combine separately compiled modules into one unit without recompilation, such as calling conventions, machine interface, and operating-system interface. Among other things, an ABI defines the binary interface between these units. ... The benefits of conforming to an ABI are that it allows linking object files compiled by different compilers. From Wikipedia: an application binary interface (ABI) describes the low-level interface between an application (or any type of) program and the operating system or another application. ABIs cover details such as data type, size, and alignment; the calling convention, which controls how functions' arguments are passed and return values retrieved; the system call numbers and how an application should make system calls to the operating system; and in the case of a complete operating system ABI, the binary format of object files, program libraries and so on. I was wondering whether ABI depends on both the instruction set and the OS. Are the two all that ABI depends on? What kinds of role does ABI play in different stages of compilation: preprocessing, conversion of code from C to Assembly, conversion of code from Assembly to Machine code, and linking? From the first quote above, it seems to me that ABI is needed for only linking stage, not the other stages. Is it correct? When is ABI needed to be considered? Is ABI needed to be considered during programming in C, Assembly or other languages? If yes, how are ABI and API different? Or is it only for linker or compiler? Is ABI specified for/in machine code, Assembly language, and/or of C?

  Read the article

• Google analytics set up with wrong domain

  - by Tom

  I have recently embedded Google Analytics into a site using the default embed code. <script> (function (i, s, o, g, r, a, m) { i['GoogleAnalyticsObject'] = r; i[r] = i[r] || function () { (i[r].q = i[r].q || []).push(arguments) }, i[r].l = 1 * new Date(); a = s.createElement(o), m = s.getElementsByTagName(o)[0]; a.async = 1; a.src = g; m.parentNode.insertBefore(a, m) })(window, document, 'script', '//www.google-analytics.com/analytics.js', 'ga'); ga('create', 'UA-XXXXXXXX-1', 'MYDOMAIN.COM'); ga('send', 'pageview'); </script> However I had MYDOMAIN.COM set to an incorrect domain. The views for the site seem very low, however, I can see myself there as a visitor in the real time scanner. What effect would setting the domain incorrectly have had? How does Google use this parameter?

  Read the article

• Do objects maintain identity under all non-cloning conditions in PHP?

  - by Buttle Butkus

  PHP 5.5 I'm doing a bunch of passing around of objects with the assumption that they will all maintain their identities - that any changes made to their states from inside other objects' methods will continue to hold true afterwards. Am I assuming correctly? I will give my basic structure here. class builder { protected $foo_ids = array(); // set in construct protected $foo_collection; protected $bar_ids = array(); // set in construct protected $bar_collection; protected function initFoos() { $this->foo_collection = new FooCollection(); foreach($this->food_ids as $id) { $this->foo_collection->addFoo(new foo($id)); } } protected function initBars() { // same idea as initFoos } protected function wireFoosAndBars(fooCollection $foos, barCollection $bars) { // arguments are passed in using $this->foo_collection and $this->bar_collection foreach($foos as $foo_obj) { // (foo_collection implements IteratorAggregate) $bar_ids = $foo_obj->getAssociatedBarIds(); if(!empty($bar_ids) ) { $bar_collection = new barCollection(); // sub-collection to be a component of each foo foreach($bar_ids as $bar_id) { $bar_collection->addBar(new bar($bar_id)); } $foo_obj->addBarCollection($bar_collection); // now each foo_obj has a collection of bar objects, each of which is also in the main collection. Are they the same objects? } } } } What has me worried is that foreach supposedly works on a copy of its arrays. I want all the $foo and $bar objects to maintain their identities no matter which $collection object they become of a part of. Does that make sense?

  Read the article

• Should we test all our methods?

  - by Zenzen

  So today I had a talk with my teammate about unit testing. The whole thing started when he asked me "hey, where are the tests for that class, I see only one?". The whole class was a manager (or a service if you prefer to call it like that) and almost all the methods were simply delegating stuff to a DAO so it was similar to: SomeClass getSomething(parameters) { return myDao.findSomethingBySomething(parameters); } A kind of boilerplate with no logic (or at least I do not consider such simple delegation as logic) but a useful boilerplate in most cases (layer separation etc.). And we had a rather lengthy discussion whether or not I should unit test it (I think that it is worth mentioning that I did fully unit test the DAO). His main arguments being that it was not TDD (obviously) and that someone might want to see the test to check what this method does (I do not know how it could be more obvious) or that in the future someone might want to change the implementation and add new (or more like "any") logic to it (in which case I guess someone should simply test that logic). This made me think, though. Should we strive for the highest test coverage %? Or is it simply an art for art's sake then? I simply do not see any reason behind testing things like: getters and setters (unless they actually have some logic in them) "boilerplate" code Obviously a test for such a method (with mocks) would take me less than a minute but I guess that is still time wasted and a millisecond longer for every CI. Are there any rational/not "flammable" reasons to why one should test every single (or as many as he can) line of code?

  Read the article

• Quickly ubuntu-application + indicator template don't work

  - by aliasbody

  I've started to work with quickly and python (because I wanted to have some GTk3 integration and create and appindicator), and so I create the projecto like this : quickly create ubuntu-application ualarm cd ualarm quickly run And the application launched. But then I tried to add the appindicator like this : quickly add indicator And since then the application doesn't start anymore and this error appear : aliasbody@BodyUbuntu-PC:~/Projectos/ualarm$ quickly run (ualarm:8515): Gtk-WARNING **: Theme parsing error: gnome-panel.css:28:11: Not using units is deprecated. Assuming 'px'. /usr/lib/python2.7/dist-packages/gi/overrides/Gtk.py:391: Warning: g_object_set_property: construct property "type" for object `Window' can't be set after construction Gtk.Window.__init__(self, type=type, **kwds) Traceback (most recent call last): File "bin/ualarm", line 33, in <module> ualarm.main() File "/home/aliasbody/Projectos/ualarm/ualarm/__init__.py", line 33, in main window = UalarmWindow.UalarmWindow() File "/home/aliasbody/Projectos/ualarm/ualarm_lib/Window.py", line 35, in __new__ new_object.finish_initializing(builder) File "/home/aliasbody/Projectos/ualarm/ualarm/UalarmWindow.py", line 24, in finish_initializing super(UalarmWindow, self).finish_initializing(builder) File "/home/aliasbody/Projectos/ualarm/ualarm_lib/Window.py", line 75, in finish_initializing self.indicator = indicator.new_application_indicator(self) File "/home/aliasbody/Projectos/ualarm/ualarm/indicator.py", line 52, in new_application_indicator ind = Indicator(window) File "/home/aliasbody/Projectos/ualarm/ualarm/indicator.py", line 20, in __init__ self.indicator = AppIndicator3.Indicator('ualarm', '', AppIndicator3.IndicatorCategory.APPLICATION_STATUS) TypeError: GObject.__init__() takes exactly 0 arguments (3 given) How can I solve this problem ?

  Read the article

< Previous Page | 68 69 70 71 72 73 74 75 76 77 78 79  | Next Page >