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Difference between abstraction and encapsulation?
...s way of saying “I don't care about the type of data” (this is also called type erasure). The important point is that the implementation of qsort always stays the same, regardless of data type. The only thing that has to change is the compare function, which differs from data type to data type. ...
How do SQL EXISTS statements work?
...hen tries to match this 'true/false' condition with outerquery." is what really cleared it up for me, I keep thinking that's how subqueries work (and many times they do), but what you said makes sense because the subquery relies on the outer query and therefore must be executed once per row
...
What is the JavaScript version of sleep()?
...e 2009 when this question was asked, JavaScript has evolved significantly. All other answers are now obsolete or overly complicated. Here is the current best practice:
function sleep(ms) {
return new Promise(resolve => setTimeout(resolve, ms));
}
async function demo() {
console.log...
IEnumerable vs List - What to Use? How do they work?
... until you enumerate it? Consider this:
public IEnumerable<Animals> AllSpotted()
{
return from a in Zoo.Animals
where a.coat.HasSpots == true
select a;
}
public IEnumerable<Animals> Feline(IEnumerable<Animals> sample)
{
return from a in sample
...
Appropriate hashbang for Node.js scripts
...tching back and forth between OS X and Ubuntu. In the former, Node is installed as node , but in the latter it is nodejs . At the top of my script, I can have:
...
Python: json.loads returns items prefixing with 'u'
...
Mark Amery
98.9k4848 gold badges336336 silver badges379379 bronze badges
answered Dec 18 '12 at 19:46
jdijdi
...
Alternative to iFrames with HTML5
...
98
Basically there are 4 ways to embed HTML into a web page:
<iframe> An iframe's content ...
Node.js spawn child process and get terminal output live
...n command that Node.js can resolve against your system path.
1. Provide a callback to process the buffered output:
var child = require('child_process').execFile('path/to/script', [
'arg1', 'arg2', 'arg3',
], function(err, stdout, stderr) {
// Node.js will invoke this callback when process...
PHP Regex to check date is in YYYY-MM-DD format
...ing to be more fuss -- and February 29 cannot be validated with a regex at all.
The drawback of this approach is that you have to be very careful to reject all possible "bad" inputs while not emitting a notice under any circumstances. Here's how:
explode is limited to return 3 tokens (so that if ...
Purging file from Git repo failed, unable to create new backup
...can find those in .git/refs/original/…. Either delete that directory and all files within, or use the -f flag to force Git to delete the old references.
git filter-branch -f \
--index-filter 'git rm --cached --ignore-unmatch Rakefile' HEAD
...