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How do I test for an empty JavaScript object?
...bject's prototype. obj.constructor can be easily forged. Example: function Foo() {} Foo.prototype.constructor = Object; (new Foo()).constructor === Object // true.
– Jesse
Apr 9 '18 at 9:22
...
The property 'value' does not exist on value of type 'HTMLElement'
...ent. Similarly in statically typed Java this won't compile:
public Object foo() {
return 42;
}
foo().signum();
signum() is a method of Integer, but the compiler only knows the static type of foo(), which is Object. And Object doesn't have a signum() method.
But the compiler can't know that, i...
Return first N key:value pairs from dict
...ts as
import itertools
import collections
d = collections.OrderedDict((('foo', 'bar'), (1, 'a'), (2, 'b'), (3, 'c'), (4, 'd')))
x = itertools.islice(d.items(), 0, 4)
for key, value in x:
print key, value
itertools.islice allows you to lazily take a slice of elements from any iterator. If yo...
How do Third-Party “tracking cookies” work?
...com, then the response might come back with a header that says Set-Cookie: foo=bar. Your browser stores this cookie, and on any subsequent requests to http://example.com, your browser will send foo=bar in the Cookie header. (Or at least until the cookie expires or is deleted.) The browser sends the ...
Create new tmux session from inside a tmux session
...se you'll get a nesting error.
$ tmux new -s development -d
$ tmux new -s foo -d
$ tmux ls
> development: 1 windows (created Wed Jan 13 11:31:38 2016) [204x54]
> foo: 1 windows (created Wed Jan 13 11:31:38 2016) [204x54]
$ tmux attach -t
$ tmux ls
> development: 1 windows (created Wed Jan ...
Using the Swift if let with logical AND operator &&
... or declaration. You can't have both expression and declaration.
let foo = bar is a declaration, it doesn't evaluate to a value that conforms to BooleanType. It declares a constant/variable foo.
Your original solution is good enough, it is much more readable then combining the conditions.
...
AngularJS: How to clear query parameters in the URL?
...
viewModelHelper.navigateTo('foo/'); was persisting the query string to the foo url, so i fixed it by using window.location.href = 'foo/'; instead.
– jaybro
Sep 2 '15 at 18:33
...
What does “javascript:void(0)” mean?
...e a control you can click on that opens up a previously-hidden <div id="foo">, it makes some sense to use <a href="#foo"> to link to it. Or if there is a non-JavaScript way of doing the same thing (for example, ‘thispage.php?show=foo’ that sets foo visible to begin with), you can lin...
How do I return early from a rake task?
...ich in a rake task has the same effect of using return in a method.
task :foo do
puts "printed"
next
puts "never printed"
end
Or you can move the code in a method and use return in the method.
task :foo do
do_something
end
def do_something
puts "startd"
return
puts "end"
end
I p...
Run a single migration file
... ruby file:
rails console
>> require "db/migrate/20090408054532_add_foos.rb"
>> AddFoos.up
Note: newer versions of rails may require AddFoos.new.up rather than AddFoos.up.
An alternative way (without IRB) which relies on the fact that require returns an array of class names:
script/...