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Why switch is faster than if
...
Because there are special bytecodes that allow efficient switch statement evaluation when there are a lot of cases.
If implemented with IF-statements you would have a check, a jump to the next clause, a check, a jump to the next clause and so on. Wit...
Convert float to double without losing precision
...ubleToRawLongBits(d3)));
You can see the float is expanded to the double by adding 0s to the end, but that the double representation of 0.27 is 'more accurate', hence the problem.
111110100010100011110101110001
11111111010001010001111010111000100000000000000000000000000000
11111111010001010001...
How to generate an openSSL key using a passphrase from the command line?
...out pass:foobar 3072
However, note that this passphrase could be grabbed by any other process running on the machine at the time, since command-line arguments are generally visible to all processes.
A better alternative is to write the passphrase into a temporary file that is protected with file ...
What does the `#` operator mean in Scala?
...hich means a B nested class of any instance of A.
We can see this in work by changing the code above:
class A {
class B
def f(b: B) = println("Got my B!")
def g(b: A#B) = println("Got a B.")
}
And trying it out:
scala> val a1 = new A
a1: A = A@1497b7b1
scala> val a2 = new A
a2: A ...
What's the difference between “Request Payload” vs “Form Data” as seen in Chrome dev tools Network t
...e more precise: payload body of a HTTP Request
- is the data normally send by a POST or PUT Request.
It's the part after the headers and the CRLF of a HTTP Request.
A request with Content-Type: application/json may look like this:
POST /some-path HTTP/1.1
Content-Type: application/json
{ "foo" : ...
How do I get the current date and time in PHP?
...
The time would go by your server time. An easy workaround for this is to manually set the timezone by using date_default_timezone_set before the date() or time() functions are called to.
I'm in Melbourne, Australia so I have something like th...
C# if/then directives for debug vs release
...
By default, Visual Studio defines DEBUG if project is compiled in Debug mode and doesn't define it if it's in Release mode. RELEASE is not defined in Release mode by default. Use something like this:
#if DEBUG
// debug stu...
Using IoC for Unit Testing
... in a huge solution (50+ projects) using IoC?
I'm not sure what you mean by managing mocks using IoC. Anyway, IoC containers can usually do more than just injecting mocks when it comes to testing. And if you have decent IDE support that makes refactoring possible, why not using it?
Any experie...
What is the difference between Lisp-1 and Lisp-2?
...
You might like to read this paper by Richard Gabriel. It is a summary of the issues that the Lisp community were discussing in Lisp1 vs Lisp2. It's a bit dense and slow moving in the first few sections, but is much easier to read by the time you get past sec...
Async/Await vs Threads
...a transfer it generates a completion notification callback. Networking is by far the most common usage, latencies of hundreds of milliseconds are common and an inevitable side-effect of services moving from the desktop or a LAN into "the cloud". Using such services synchronously would make a UI qu...