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What is the id( ) function used for?
I read the Python 2 docs and noticed the id() function:
13 Answers
13
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How to remove the first and the last character of a string
I'm wondering how to remove the first and last character of a string in Javascript.
9 Answers
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How to check for an undefined or null variable in JavaScript?
...xistingObj.someUndefProperty. An undefined property doesn't yield an error and simply returns undefined, which, when converted to a boolean, evaluates to false. So, if you don't care about
0 and false, using if(obj.undefProp) is ok. There's a common idiom based on this fact:
value = obj.prop || de...
Hidden features of Windows batch files
What are some of the lesser know, but important and useful features of Windows batch files?
91 Answers
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How to explain callbacks in plain english? How are they different from calling one function from ano
...on will set this variable with the information about function to be called and will call the function using the same variable.
In javascript, the example is below. Here we use method argument as a variable where we store information about function.
function processArray(arr, callback) {
var re...
Difference between Destroy and Delete
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ActiveRecord::Persistence.delete
Deletes the record in the database and freezes this instance to reflect that no changes should be made (since they can't be persisted). Returns the frozen instance.
The row is simply removed with an SQL DELETE statement on the record's primary key, and no...
Fast way to get image dimensions (not filesize)
I'm looking for a fast way to get the height and width of an image in pixels. It should handle at least JPG, PNG and TIFF, but the more the better. I emphasize fast because my images are quite big (up to 250 MB) and it takes soooo long to get the size with ImageMagick's identify because it obv...
How to swap two variables in JavaScript
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Here's a one-liner to swap the values of two variables.
Given variables a and b:
b = [a, a = b][0];
Demonstration below:
var a=1,
b=2,
output=document.getElementById('output');
output.innerHTML="<p>Original: "+a+", "+b+"</p>";
b = [a, a = b][0];
output.innerHT...
What is the difference between 'java', 'javaw', and 'javaws'?
What is the difference between java , javaw , and javaws ?
5 Answers
5
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Difficulty with ng-model, ng-repeat, and inputs
I am trying to allow the user to edit a list of items by using ngRepeat and ngModel . ( See this fiddle .) However, both approaches I've tried lead to bizarre behavior: one doesn't update the model, and the other blurs the form on each keydown.
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