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Why is using “for…in” for array iteration a bad idea?
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for (var i = 0; i < a.length; i++) {
// Iterate over numeric indexes from 0 to 5, as everyone expects.
console.log(a[i]);
}
/* Will display:
undefined
undefined
undefined
undefined
undefined
5
*/
can sometimes be totally different from the other:
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is there a Java equivalent to null coalescing operator (??) in C#? [duplicate]
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Sadly - no. The closest you can do is:
int y = (x != null) ? x : -1;
Of course, you can wrap this up in library methods if you feel the need to (it's unlikely to cut down on length much), but at the syntax level there isn't anything more succinct available.
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How to calculate the number of occurrence of a given character in each row of a column of strings?
I have a data.frame in which certain variables contain a text string. I wish to count the number of occurrences of a given character in each individual string.
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Determine which element the mouse pointer is on top of in JavaScript
...mentFromPoint which does what it sounds like.
What we need is to find the x and y coords of the mouse and then call it using those values:
var x = event.clientX, y = event.clientY,
elementMouseIsOver = document.elementFromPoint(x, y);
document.elementFromPoint
jQuery event object
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How to determine if one array contains all elements of another array
... @Chris - You could try using Array#uniq for that. With Holger Just's example, it would be (a2.uniq - a1.uniq).empty?
– Nick
Dec 4 '12 at 17:07
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Is it possible to install APK file if more than one emulators/devices are connected [duplicate]
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yes, the number you are getting after executing adb devices
– Mohammed Azharuddin Shaikh
Aug 25 '11 at 7:09
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Array slicing in Ruby: explanation for illogical behaviour (taken from Rubykoans.com)
I was going through the exercises in Ruby Koans and I was struck by the following Ruby quirk that I found really unexplainable:
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Can C++ code be valid in both C++03 and C++11 but do different things?
...ll now implicitly move them when possible.
On the negative side, several examples are listed in the appendix C of the standard. Even though there are many more negative ones than positive, each one of them is much less likely to occur.
String literals
#define u8 "abc"
const char* s = u8"def"; // Pr...
Ignore Typescript Errors “property does not exist on value of type”
In VS2013 building stops when tsc exits with code 1. This was not the case in VS2012.
10 Answers
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Method Resolution Order (MRO) in new-style classes?
In the book Python in a Nutshell (2nd Edition) there is an example which uses
old style classes to demonstrate how methods are resolved in classic resolution order and
how is it different with the new order.
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