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What is the instanceof operator in JavaScript?
...there.
Every object in JavaScript has a prototype, accessible through the __proto__ property. Functions also have a prototype property, which is the initial __proto__ for any objects created by them. When a function is created, it is given a unique object for prototype. The instanceof operator uses...
Using module 'subprocess' with timeout
...
In Python 3.3+:
from subprocess import STDOUT, check_output
output = check_output(cmd, stderr=STDOUT, timeout=seconds)
output is a byte string that contains command's merged stdout, stderr data.
check_output raises CalledProcessError on non-zero exit status as specified i...
Foreign keys in mongo?
...his:
class Student
include Mongoid::Document
field :name
embeds_many :addresses
embeds_many :scores
end
class Address
include Mongoid::Document
field :address
field :city
field :state
field :postalCode
embedded_in :student
end
class Score
include Mongoi...
How does __proto__ differ from constructor.prototype?
...bject layout
The most surprising thing for me was discovering that Object.__proto__ points to Function.prototype, instead of Object.prototype, but I'm sure there's a good reason for that :-)
I paste the code mentioned in the image here as well for if anyone wants to test it. Note that some propert...
Iterate an iterator by chunks (of n) in Python? [duplicate]
...', 'x') --> ABC DEF Gxx"
args = [iter(iterable)] * n
return izip_longest(fillvalue=fillvalue, *args)
It will fill up the last chunk with a fill value, though.
A less general solution that only works on sequences but does handle the last chunk as desired is
[my_list[i:i + chunk_size] f...
How do I count a JavaScript object's attributes? [duplicate]
...
Use underscore library, very useful: _.keys(obj).length.
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“x not in y” or “not x in y”
...am' not in 'spam and eggs'
>>> dis.dis(notin)
2 0 LOAD_CONST 1 ('ham')
3 LOAD_CONST 2 ('spam and eggs')
6 COMPARE_OP 7 (not in)
9 POP_TOP
10 LOAD_CONST 0 (...
How do I watch a file for changes?
...ooked at the documentation available on http://timgolden.me.uk/python/win32_how_do_i/watch_directory_for_changes.html? If you only need it to work under Windows the 2nd example seems to be exactly what you want (if you exchange the path of the directory with the one of the file you want to watch).
...
How to open a URL in a new Tab using JavaScript or jQuery? [duplicate]
...
Use window.open():
var win = window.open('http://stackoverflow.com/', '_blank');
if (win) {
//Browser has allowed it to be opened
win.focus();
} else {
//Browser has blocked it
alert('Please allow popups for this website');
}
Depending on the browsers implementation this will w...
How to download a file from a URL in C#?
...ethod also supports local files as 1st parameter
– oo_dev
Aug 22 '17 at 8:35
The MSDN doc did mention to use HttpClien...