#language-agnostic

What is dependency injection?

Dependency Injection is passing dependency to other objects or framework( dependency injector). Dependency injection makes testing easier. The injection can be done through constructor. SomeClass() has its constructor as following: public SomeClass() { myObject = Factory.getObject(); } Problem: If myObject involves complex tasks such as disk access or network access, it is hard to do unit…

Resolved: Can I read the hash portion of the URL on my server-side application (PHP, Ruby, Python, etc.) #it #answer #computers

Can I read the hash portion of the URL on my server-side application (PHP, Ruby, Python, etc.)

Assuming a URL of:

www.mysite.com?val=1#part2

PHP can read the request variables “val1″ using the GET array.

Is the hash value part2 also readable? or is this only upto the browser and JavaScript.

Answer [by PatrikAkerstrand]: Can I read the hash portion of the URL on my server-side application (PHP,…

Fixed: Equation for testing if a point is inside a circle #computers #programming #answer

Equation for testing if a point is inside a circle

If you have a circle with center (center_x, center_y) and radius radius, how do you test if a given point with coordinates (x, y) is inside the circle?

Answer [by Jason]: Equation for testing if a point is inside a circle

In general, x and y must satisfy (x - center_x)^2 + (y - center_y)^2 < radius^2.

Please note that points that satisfy the…

Fixed: What is the fastest way to get the value of π? #it #computers #answer

What is the fastest way to get the value of π?

Solutions are welcome in any language. :-) I’m looking for the fastest way to obtain the value of π, as a personal challenge. More specifically I’m using ways that don’t involve using #defined constants like M_PI, or hard-coding the number in.

The program below tests the various ways I know of. The inline assembly version is, in theory, the fastest…

Fixed: Why should hash functions use a prime number modulus? #solution #it #dev

Why should hash functions use a prime number modulus?

A long time ago, I bought a data structures book off the bargain table for $1.25. In it, the explanation for a hashing function said that it should ultimately mod by a prime number because of “the nature of math”.

What do you expect from a $1.25 book?

Anyway, I’ve had years to think about the nature of math, and still can’t figure it out.

Is…

Resolved: How does Stack Overflow generate its SEO-friendly URLs? #it #computers #development

How does Stack Overflow generate its SEO-friendly URLs?

What is a good complete regular expression or some other process that would take the title:

How do you change a title to be part of the URL like Stack Overflow?

and turn it into

how-do-you-change-a-title-to-be-part-of-the-url-like-stack-overflow

that is used in the SEO-friendly URLs on Stack Overflow?

The development environment I am…

Answer: Why is processing a sorted array slower than an unsorted array? #dev #computers #answer

Why is processing a sorted array slower than an unsorted array?

I have a list of 500000 randomly generated Tuple<long,long,string> objects on which I am performing a simple “between” search:

var data = new List<Tuple<long,long,string>>(500000); ... var cnt = data.Count(t => t.Item1 <= x && t.Item2 >= x);

When I generate my random array and run my search for 100 randomly generated values of x,…

How-to: What's the shortest code to cause a stack overflow? #it #dev #solution

What’s the shortest code to cause a stack overflow?

To commemorate the public launch of Stack Overflow, what’s the shortest code to cause a stack overflow? Any language welcome.

ETA: Just to be clear on this question, seeing as I’m an occasional Scheme user: tail-call “recursion” is really iteration, and any solution which can be converted to an iterative solution relatively trivially by a…