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How to validate an email address using a regular expression?
...me web page as was the address.
Confirmation tokens are the only way to know you got the address of the person entering it. This is why most mailing lists now use that mechanism to confirm sign-ups. After all, anybody can put down president@whitehouse.gov, and that will even parse as legal, but it...
What is the most effective way for float and double comparison?
...the order of operations can produce different results, it is important to know how "equal" you want the numbers to be.
Comparing floating point numbers by Bruce Dawson is a good place to start when looking at floating point comparison.
The following definitions are from The art of computer progr...
Why isn't String.Empty a constant?
...tring.Empty read only instead of a constant? I'm just wondering if anyone knows what the reasoning was behind that decision.
...
Flags to enable thorough and verbose g++ warnings
...re present:
I include -Wno-unused because I often have variables that I know I
will use later, but do not yet have the functionality written for.
Removing warnings about that allows me to write in my preferred style
of occasionally deferring the implementation of things. It is useful
to turn that ...
Useless use of cat?
...single greps you learn the placement of the file argument and it is ready knowledge that the first is the pattern and the later ones are file names.
It was a conscious choice to use cat when I answered the question, partly because of a reason of "good taste" (in the words of Linus Torvalds) but chi...
Undefined, unspecified and implementation-defined behavior
...clude <iostream>
int main()
{
char* p = "hello!\n"; // yes I know, deprecated conversion
p[0] = 'y';
p[5] = 'w';
std::cout << p;
}
The variable p points to the string literal "hello!\n", and the two assignments below try to modify that string literal. What does this p...
What are the differences between Clojure, Scheme/Racket and Common Lisp?
I know they are dialects of the same family of language called lisp, but what exactly are the differences? Could you give an overview, if possible, covering topics such as syntax, characteristics, features and resources.
...
Are HLists nothing more than a convoluted way of writing tuples?
...tions for HLists is abstracting over arity. Arity is typically statically known at any given use site of an abstraction, but varies from site to site. Take this, from shapeless's examples,
def flatten[T <: Product, L <: HList](t : T)
(implicit hl : HListerAux[T, L], flatten : Flatten[L]) : ...
How do I choose grid and block dimensions for CUDA kernels?
...rion to choose the block size, it would be worth mentioning that CUDA 6.5 (now in Release Candidate version) includes several new runtime functions to aid in occupancy calculations and launch configuration, see
CUDA Pro Tip: Occupancy API Simplifies Launch Configuration
One of the useful functions...
C# listView, how do I add items to columns 2, 3 and 4 etc?
...FullRowSelect = true"... otherwise only column 1 is clickable. I wish I'd known this earlier! it would have saved me a ton of work.
– John Henckel
Jun 1 '15 at 15:18
...