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What is the difference between atomic / volatile / synchronized?
...ed and are not interrupted by other threads. For example, an increment-and-test operation requires the variable to be incremented and then compared to another value; an atomic operation guarantees that both of these steps will be completed as if they were a single indivisible/uninterruptible operati...
What's the right way to pass form element state to sibling/parent elements?
...onent {
constructor (props) {
super(props)
this.state = { data: 'test' }
}
render () {
return (
<div>
<C1 onUpdate={this.onUpdate.bind(this)}/>
<C2 data={this.state.data}/>
</div>
)
}
onUpdate (data) { this.setState({ data...
Why are joins bad when considering scalability?
...op of the list. A lot of (cough) developers seem to forget about them when testing on a small data set and then bring the database to its knees in production. I have seen queries that run to the order of 100,000 times faster simply by adding indexes. And that's arbitrary indexes without even doing a...
Load and execution sequence of a web page?
...ple when the parser comes across this line:
<a href="#" onclick="alert('test');return false;" style="font-weight:bold">a hypertext link</a>
The parser will make 3 calls, two to Javascript and one to CSS. Firstly, the parser will create this element and register it in the DOM namespace, ...
Why are side-effects modeled as monads in Haskell?
...
In short, the greatest lower bound on what all monads together describe is a blind, meaningless march into the future. IO is a pathological case precisely because it offers almost nothing more than this minimum. In specific cases, types may re...
Why doesn't C# support the return of references?
...s not a huge amount of dev work to do so, but it is a lot of burden on the testing teams to make sure that we've really got all the cases. It's just another thing that increases the cost of the feature to the point where right now the benefits do not outweigh the costs.
If you can describe for me w...
Setting environment variables via launchd.conf no longer works in OS X Yosemite/El Capitan/macOS Sie
...dit]: A user below mentions that this did not work for him. However I have tested on multiple Yosemite machines and it does work for me. If you are having a problem, remember that you will need to restart applications for this to take effect. Additionally if you set variables in the terminal via ~/....
What is the function of the push / pop instructions used on registers in x86 assembly?
... stored.
Ideally, all variables would fit into registers, which is the fastest memory to access (currently about 100x faster than RAM).
But of course, we can easily have more variables than registers, specially for the arguments of nested functions, so the only solution is to write to memory.
We ...
Evaluating a mathematical expression in a string
... "sgn": lambda a: abs(a) > epsilon and cmp(a, 0) or 0}
def evaluateStack(self, s):
op = s.pop()
if op == 'unary -':
return -self.evaluateStack(s)
if op in "+-*/^":
op2 = self.evaluateStack(s)
op1 = self.evaluateStack(s)
...
C++ Modules - why were they removed from C++0x? Will they be back later on?
...ion have been published by WG21 on open-std.org. I will link only to the latest documents here:
Working Draft, Extensions to C++ for Modules N4610 (October 2016).
Fourth revision published as P0142R0 (March 2016).
Wording for Modules published as P0143R2 (March 2016).
The clang team has published ...