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Get operating system info
I recently started wondering about sites like http://thismachine.info/ that get the user's operating system info. I have not been able to find out how to do that with PHP, and wanted to try to figure it out.
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Best explanation for languages without null
...+
p.middleName.map{length}.getOrElse(0) +
p.lastName.length
When you start dealing with List of Options, it gets even better. Imagine that the List people is itself optional:
people flatMap(_ find (_.firstName == "joe")) map (fullNameLength)
How does this work?
//convert an Option[List[Pe...
How to explain callbacks in plain english? How are they different from calling one function from ano
...e the term "callback" makes the most obvious sense. Once an i/o process is started (like asking for a file to be read from disk or a server to return data from an http request) an asynchronous program doesn't wait around for it to finish. It can go ahead with whatever tasks are scheduled next, and o...
What are the differences between NP, NP-Complete and NP-Hard?
...e coloured using two colours so that no edge is monochromatic?
Algorithm: start with an arbitrary vertex, color it red and all of its neighbours blue and continue. Stop when you run out of vertices or you are forced to make an edge have both of its endpoints be the same color.
NP
NP is a comple...
How do CDI and EJB compare? interact?
...rify from an EJB spec perspective we made the deliberate decision from the start of CDI to require that EJB implementations must support 100% of the CDI feature set on EJBs. Every aspect of CDI works on EJBs with the exception of scopes which we had to limit to Stateful beans only.
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Lock-free multi-threading is for real threading experts
...ving this from a single thread. You will, however run into issues when you start to do multi-threading on multiple cores. Your intuitions will break down: just because an instruction is earlier in your code, it does not mean that it will actually happen earlier. CPUs can process instructions out of ...
Cookie blocked/not saved in IFRAME in Internet Explorer
...e cookies will be accepted.
How to solve it
Create a p3p policy
A good starting point is the W3C tutorial. I've gone through it, downloaded the IBM Privacy Policy Editor and there I created a representation of the privacy policy and gave it a name to reference it by (here it was policy1).
NOTE...
Referring to the null object in Python
... in a way that it can't.
Also, None is a built-in constant. As soon as you start Python, it's available to use from everywhere, whether in module, class, or function. NoneType by contrast is not, you'd need to get a reference to it first by querying None for its class.
>>> NoneType
NameErro...
What are the advantages of using nullptr?
...w and where should you use nullptr?
The rule of thumb for C++11 is simply start using nullptr whenever you would have otherwise used NULL in the past.
Standard References:
C++11 Standard: C.3.2.4 Macro NULL
C++11 Standard: 18.2 Types
C++11 Standard: 4.10 Pointer conversions
C99 Standard: 6.3....
What is the most effective way for float and double comparison?
...o 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 programming by Knuth:
bool approximatelyEqual(float a, float b, float epsilon)
{
return fabs(a - b) <= ( (fab...