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Why is “copy and paste” of code dangerous? [closed]
...you will need to fix it every place you did and hope you can remember them all (this also holds for changed requirements).
If you keep logic in one place, it is easier to change when needed (so if you decide that the application needs updating, you only do it in one place).
Have your boss read abo...
Opposite of %in%: exclude rows with values specified in a vector
... use
`%not in%` <- function (x, table) is.na(match(x, table, nomatch=NA_integer_))
Another way is:
function (x, table) match(x, table, nomatch = 0L) == 0L
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Is the order of iterating through std::map known (and guaranteed by the standard)?
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Yes, that's guaranteed. Moreover, *begin() gives you the smallest and *rbegin() the largest element, as determined by the comparison operator, and two key values a and b for which the expression !compare(a,b) && !compare(b,a) is true are considered equal. The default comparis...
Why is UICollectionViewCell's outlet nil?
...I don't use it, it gives me error Assertion failure in -[UICollectionView _dequeueReusableViewOfKind:withIdentifier:forIndexPath:viewCategory:]
– Shaheera
Jun 30 '16 at 11:04
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How to sort a collection by date in MongoDB?
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@SamBrightman That function is just a callback. Whatever you want to do with the query result, you put that logic inside your callback. You can read more on what callbacks are and how they work to learn event based programming.
– Sushant Gupt...
How to check what user php is running as?
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If available you can probe the current user account with posix_geteuid and then get the user name with posix_getpwuid.
$username = posix_getpwuid(posix_geteuid())['name'];
If you are running in safe mode however (which is often the case when exec is disabled), then it's unlikely tha...
Return JSON response from Flask view
...om flask import jsonify
@app.route('/summary')
def summary():
d = make_summary()
return jsonify(d)
As of Flask 0.11, you can pass any JSON-serializable type, not just dict, as the top level object.
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How do I install a custom font on an HTML site
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Yes, you can use the CSS feature named @font-face.
It has only been officially approved in CSS3, but been proposed and implemented in CSS2 and has been supported in IE for quite a long time.
You declare it in the CSS like this:
@font-face { font-family: Delicious; src: url('Delicious-Roman.otf')...
What is CDATA in HTML? [duplicate]
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All text in an XML document will be parsed by the parser.
But text inside a CDATA section will be ignored by the parser.
CDATA - (Unparsed) Character Data
The term CDATA is used about text data that should not be parsed by t...
Swift: declare an empty dictionary
...ou have to be explicit, otherwise you will produce an unusable instance of __NSDictionaryI. Try adding an element to that emptyDict and it will fail at compile time.
– Gabriele Petronella
Jun 4 '14 at 13:34
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