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How to iterate over a JavaScript object?
I have an object in JavaScript:
18 Answers
18
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What is a “callable”?
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A callable is anything that can be called.
The built-in callable (PyCallable_Check in objects.c) checks if the argument is either:
an instance of a class with a __call__ method or
is of a type that has a non null tp_call (c stru...
Get all non-unique values (i.e.: duplicate/more than one occurrence) in an array
...the same as the current. Assuming your sort algorithm is good, this should be less than O(n2):
const findDuplicates = (arr) => {
let sorted_arr = arr.slice().sort(); // You can define the comparing function here.
// JS by default uses a crappy string compare.
// (we use slice to cl...
CSS3 Rotate Animation
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Here is a demo. The correct animation CSS:
.image {
position: absolute;
top: 50%;
left: 50%;
width: 120px;
height: 120px;
margin:-60px 0 0 -60px;
-webkit-animation:spin 4s linear infinite;
-moz-animation:spin 4s linear infinite;
animation:spin 4s l...
What is the most pythonic way to check if an object is a number?
Given an arbitrary python object, what's the best way to determine whether it is a number? Here is is defined as acts like a number in certain circumstances .
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Capitalize words in string [duplicate]
What is the best approach to capitalize words in a string?
21 Answers
21
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Shortest distance between a point and a line segment
I need a basic function to find the shortest distance between a point and a line segment. Feel free to write the solution in any language you want; I can translate it into what I'm using (Javascript).
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Changing UIImage color
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Since iOS 7, this is the most simple way of doing it.
Objective-C:
theImageView.image = [theImageView.image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
[theImageView setTintColor:[UIColor redColor]];
Swift 2.0:
theImageView.image = theImageView.image?.imageWit...
Get exception description and stack trace which caused an exception, all as a string
I've seen a lot of posts about stack trace and exceptions in Python. But haven't found what I need.
11 Answers
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What's wrong with nullable columns in composite primary keys?
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Primary keys are for uniquely identifying rows. This is done by comparing all parts of a key to the input.
Per definition, NULL cannot be part of a successful comparison. Even a comparison to itself (NULL = NULL) will fail. This means a key containing NULL would not work.
Additonall...