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“var” or no “var” in JavaScript's “for-in” loop?
...s can lead to problems like the following.
function f (){
for (i=0; i<5; i++);
}
var i = 2;
f ();
alert (i); //i == 5. i should be 2
If you write var i in the for loop the alert shows 2.
JavaScript Scoping and Hoisting
...
What is the difference between bottom-up and top-down?
...the recursive call never recomputes a subproblem because you cache the results, and thus duplicate sub-trees are not recomputed.
example: If you are calculating the Fibonacci sequence fib(100), you would just call this, and it would call fib(100)=fib(99)+fib(98), which would call fib(99)=fib(98)+f...
Most efficient way to convert an HTMLCollection to an Array
...ides the spread operator, which is functionally equivalent to Array.from (although note that Array.from supports a mapping function as the second argument).
var arr = [...htmlCollection];
I've confirmed that both of the above work on NodeList.
A performance comparison for the mentioned methods: ...
Clearing a string buffer/builder after loop
...thod as follows:
StringBuffer sb = new StringBuffer();
for (int n = 0; n < 10; n++) {
sb.append("a");
// This will clear the buffer
sb.delete(0, sb.length());
}
Another option (bit cleaner) uses setLength(int len):
sb.setLength(0);
See Javadoc for more info:
...
versionCode vs versionName in Android Manifest
...subject.
"for example to check an upgrade or downgrade relationship." <- You can downgrade an app.
"you should make sure that each successive release of your application uses a greater value. The system does not enforce this behavior" <- The number really should increase, but you can stil...
Copy array items into another array
...rrayB remain unchanged; concat creates and returns a new array for the result).
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Removing the title text of an iOS UIBarButtonItem
... forBarMetrics:UIBarMetricsDefault];
Then you can remove the back button item title.
If you use Storyboard, you can set navigation attributes inspector Back Button with space.
...
Pro JavaScript programmer interview questions (with answers) [closed]
...d write a function that looks like this:
function sum() {
var i, l, result = 0;
for (i = 0, l = arguments.length; i < l; i++) {
result += arguments[i];
}
return result;
}
sum(1,2,3); // 6
And they should invoke it on your array like this (context for apply can be whatever, I usuall...
How to represent multiple conditions in a shell if statement?
I want to represent multiple conditions like this:
8 Answers
8
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When should I use jQuery deferred's “then” method and when should I use the “pipe” method?
...of jQuery 1.8, the deferred.then() method returns a new promise that can filter the status and values of a deferred through a function, replacing the now-deprecated deferred.pipe() method.
The examples below might still be helpful to some.
They serve different purposes:
.then() is to be used when...