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In Objective-C why should I check if self = [super init] is not nil?
... not hell bent on not following best practices. I would, however, like to know why they are best practises in the first place. Its like being told to jump off a tower. You don't just go ahead and do it unless you know why. Is there a big, soft pillow to land on at the bottom, with a massive cash rew...
How to test if parameters exist in rails
...I, but I'm sure that's safe enough. I've been calling params.to_h.key? for now.
– stephen.hanson
Nov 9 '16 at 19:38
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Dynamic array in C#
...ray();
Of course, this has sense only if the size of the array is never known nor fixed ex-ante.
if you already know the size of your array at some point of the program it is better to initiate it as a fixed length array. (If you retrieve data from a ResultSet for example, you could count its size...
Running a command in a Grunt Task
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Does anyone know if either of those two is usable on Windows?
– Capaj
Apr 25 '13 at 11:50
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“using namespace” in c++ headers
...ment. As for template functions defined in headers, unfortunately I don't know of a good solution other than just writing out the namespace... Perhaps you could put a using declaration within a separate scope { /* using statement in between brackets */ }, that would at least prevent it from escaping...
Determining whether jQuery has not found any element
...t(0) !== undefined
$('#my_selector')[0] !== undefined
This is the basic, now do whatever you want.
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Run an app on a multiple devices automatically in Android Studio
... Yes but since this question was never answered, others will now know how to do this. It isn't exactly obvious in the interface.
– damccull
Jan 22 '14 at 14:11
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How to replace an item in an array with Javascript?
...edle) {
return !!~haystack.indexOf(needle);
};
// can be used like so now:
if (contains(items, 3452)) {
// do something else...
}
Starting with ES6/ES2015 for strings, and proposed for ES2016 for arrays, you can more easily determine if a source contains another value:
if (haystack.inclu...
How do I get the difference between two Dates in JavaScript?
...g(Math.floor(((b - a) % msDay) / msMinute) + ' full minutes between');
Now some pitfalls. Try this:
console.log(a - 10);
console.log(a + 10);
So if you have risk of adding a number and Date, convert Date to number directly.
console.log(a.getTime() - 10);
console.log(a.getTime() + 10);
My f...
SVG get text element width
... div.style.width = 'auto';
div.style.whiteSpace = 'nowrap';
div.style.fontFamily = 'YOUR_FONT_GOES_HERE';
div.style.fontSize = '100';
div.style.border = "1px solid blue"; // for convenience when visible
div.innerHTML = "YO...