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How to delete items from a dictionary while iterating over it?
...--------------------------------------------------
Traceback (most recent call last):
File "<ipython console>", line 1, in <module>
RuntimeError: dictionary changed size during iteration
As stated in delnan's answer, deleting entries causes problems when the iterator tries to move on...
What is Scala's yield?
...I use yield instead of map? This map code is equivalent val res = args.map(_.toUpperCase) , right?
– Geo
Jun 27 '09 at 12:23
4
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Check if a value is an object in JavaScript
...o examine variable's properties, but it is not a bulletproof recipe (after all there's no recipe at all!) for checking whether it's an object, far from it. Since people tend to look for something to copy from here without doing any research, I'd highly recommend that they turn to the other, most upv...
Is a Python list guaranteed to have its elements stay in the order they are inserted in?
...answer so I don't want to add another. He could also use list.append to really put his mind at ease. docs.python.org/2/tutorial/datastructures.html
– NG.
Dec 4 '12 at 0:15
1
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Get difference between 2 dates in JavaScript? [duplicate]
...day. As for always returning a positive number, that was a feature :) Typically when one talks about the number of days between two dates, that number is positive. If direction matters, just remove the Math.abs().
– TNi
Jul 11 '10 at 22:38
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indexOf method in an object array?
... think to see the performance of this method vs. a simple for loop. Especially when you're running on a mobile platform with limited resources.
– Doug
Aug 17 '15 at 5:51
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How to check if object has any properties in JavaScript?
...d Apr 20 '10 at 6:49
Daniel VassalloDaniel Vassallo
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How to concatenate strings in twig
...like Alessandro said, and here it is in the documentation:
~: Converts all operands into strings and concatenates them. {{ "Hello
" ~ name ~ "!" }} would return (assuming name is 'John') Hello John!. – http://twig.sensiolabs.org/doc/templates.html#other-operators
And here is an example so...
How can I connect to a Tor hidden service using cURL in PHP?
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You need to set option CURLOPT_PROXYTYPE to CURLPROXY_SOCKS5_HOSTNAME, which sadly wasn't defined in old PHP versions, circa pre-5.6; if you have earlier in but you can explicitly use its value, which is equal to 7:
curl_setopt($ch, CURLOPT_PROXYTYPE, 7...
Difference between variable declaration syntaxes in Javascript (including global variables)?
...here are a couple of differences, though in practical terms they're not usually big ones.
There's a fourth way, and as of ES2015 (ES6) there's two more. I've added the fourth way at the end, but inserted the ES2015 ways after #1 (you'll see why), so we have:
var a = 0; // 1
let a = 0; // 1...