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How to wait until an element exists?
...atch the DOM. It's only supported in newer browsers though, so you should fall back onto DOMNodeInserted when MutationObserver isn't available.
let observer = new MutationObserver((mutations) => {
mutations.forEach((mutation) => {
if (!mutation.addedNodes) return
for (let i = 0; i &...
How can I force division to be floating point? Division keeps rounding down to 0?
... a floating point number in Python in the following?
c = a / b
What is really being asked here is:
"How do I force true division such that a / b will return a fraction?"
Upgrade to Python 3
In Python 3, to get true division, you simply do a / b.
>>> 1/2
0.5
Floor division, the classic di...
How to copy a java.util.List into another java.util.List
...rch for copying a list suggested me to use Collections.copy() method. In all the examples I saw, the destination list was supposed to contain the exact number of items for the copying to take place.
...
How do I show the value of a #define at compile-time?
...ring. When there is more than one component to the argument then they must all be strings so that string concatenation can be applied. The preprocessor can never assume that an unquoted string should be treated as if it were quoted. If it did then:
#define ABC 123
int n = ABC;
would not compile.
...
How to quickly clear a JavaScript Object?
...object).
In this example, I believe setting the length to 0 still leaves all of the elements for garbage collection.
You could add this to Object.prototype if it's something you'd frequently use. Yes it's linear in complexity, but anything that doesn't do garbage collection later will be.
This is ...
Can you set a border opacity in CSS?
...wsers do not understand the rgba format and will not display any border at all if this is the entire declaration. The solution is to provide two border declarations. The first with a fake opacity, and the second with the actual. If a browser is capable, it will use the second, if not, it will use th...
Is there a “goto” statement in bash?
...atement in bash ? I know It is considered bad practice, but I need specifically "goto".
12 Answers
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How to implement an abstract class in ruby?
I know there is no concept of abstract class in ruby. But if at all it needs to be implemented, how to go about it? I tried something like...
...
Reference — What does this symbol mean in PHP?
... have the same results.
Pre-increment is a little bit faster because it really increments the variable and after that 'returns' the result. Post-increment creates a special variable, copies there the value of the first variable and only after the first variable is used, replaces its value with seco...
How do you clone a Git repository into a specific folder?
...t/it/
mv /where/it/is/right/now/.* /where/I/want/it/
The first line grabs all normal files, the second line grabs dot-files. It is also possibe to do it in one line by enabling dotglob (i.e. shopt -s dotglob) but that is probably a bad solution if you are asking the question this answer answers.
Be...