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Why is isNaN(null) == false in JS?
...s question, but semantically it's referring specifically to the value NaN. From Wikipedia for NaN:
NaN (Not a Number) is a value of the numeric data type representing an undefined or unrepresentable value, especially in floating-point calculations.
In most cases we think the answer to "is nul...
How can I reverse a NSArray in Objective-C?
...rse any NSMutableArray in place:
/* Algorithm: swap the object N elements from the top with the object N
* elements from the bottom. Integer division will wrap down, leaving
* the middle element untouched if count is odd.
*/
for(int i = 0; i < [array count] / 2; i++) {
int j = [array co...
How to detect the current OS from Gradle
I found this answer about how to do it with Groovy:
6 Answers
6
...
What's the difference between integer class and numeric class in R
...s are whole numbers. For example, 1:5 creates an integer vector of numbers from 1 to 5. You don't need to append the letter L.
> class(1:5)
[1] "integer"
Reference: https://www.quora.com/What-is-the-difference-between-numeric-and-integer-in-R
...
Python threading.timer - repeat function every 'n' seconds
...
From Equivalent of setInterval in python:
import threading
def setInterval(interval):
def decorator(function):
def wrapper(*args, **kwargs):
stopped = threading.Event()
def loop(): # exe...
How to detect if my shell script is running through a pipe?
How do I detect from within a shell script if its standard output is being sent to a terminal or if it's piped to another process?
...
How do you know when to use fold-left and when to use fold-right?
...re you can see the traversal to the base case 4 and building up the result from there.
So I posit a rule of thumb: if it looks like a list iteration, one that would be simple to write in tail-recursive form, foldl is the way to go.
But really this will be probably be most evident from the associat...
Node.js throws “btoa is not defined” error
...eed to convert to Base64 you could do so using Buffer:
console.log(Buffer.from('Hello World!').toString('base64'));
Reverse (assuming the content you're decoding is a utf8 string):
console.log(Buffer.from(b64Encoded, 'base64').toString());
Note: prior to Node v4, use new Buffer rather than B...
What is event bubbling and capturing?
...ion:
quirksmode.org has a nice description of this. In a nutshell (copied from quirksmode):
Event capturing
When you use event capturing
| |
---------------| |-----------------
| element1 | | |
| -----------| |----------- |
| |element2 \ / ...
How to create streams from string in Node.Js?
...
From node 10.17, stream.Readable have a from method to easily create streams from any iterable (which includes array literals):
const { Readable } = require("stream")
const readable = Readable.from(["input string"])
readab...