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Deleting an object in java?
...n by the garbage collector.
myObject = null may not do it; for example:
Foo myObject = new Foo(); // 1 reference
Foo myOtherObject = myObject; // 2 references
myObject = null; // 1 reference
All this does is set the reference myObject to null, it does not affect the object myObject once pointed...
What's the yield keyword in JavaScript?
...: Generators" by James Long for the official Harmony standard:
function * foo(x) {
while (true) {
x = x * 2;
yield x;
}
}
"When you call foo, you get back a Generator object which has a next
method."
var g = foo(2);
g.next(); // -> 4
g.next(); // -> 8
g.next()...
How does the vim “write with sudo” trick work?
...ointing out that this does not evaluate to the filename). For example, :%s/foo/bar means "in the current file, replace occurrences of foo with bar." If you highlight some text before typing :s, you'll see that the highlighted lines take the place of % as your substitution range.)
:w isn't updating ...
Which characters are valid in CSS class names/selectors?
...
@Adamarla <p class="foo bar"> adds two classes to the p element: foo, and bar. There is no way (that I can think of) to add a classname containing whitespace to an HTML element. The information on how to escape whitespace characters was inclu...
How do I get the number of days between two dates in JavaScript?
... var hours = minutes*60;
var days = hours*24;
var foo_date1 = getDateFromFormat("02/10/2009", "M/d/y");
var foo_date2 = getDateFromFormat("02/12/2009", "M/d/y");
var diff_date = Math.round((foo_date2 - foo_date1)/days);
alert("Diff date i...
How to dynamically build a JSON object with Python?
...t;>> from easydict import EasyDict as edict
>>> d = edict({'foo':3, 'bar':{'x':1, 'y':2}})
>>> d.foo
3
>>> d.bar.x
1
>>> d = edict(foo=3)
>>> d.foo
3
[INSTALLATION]:
pip install easydict
...
emacs/elisp: What is the hash (pound, number sign, octothorp) symbol used for?
... printed is a description (but cannot be read). For example:
#<buffer foo.txt>
It is also used in constructs by the reader to represent circular structures. See the docs for Read Syntax for Circular Objects.
And then you have its use for denoting the base for integers, e.g. #x2c -> 44...
ALTER TABLE to add a composite primary key
...ing queries:
A) SELECT person, place, thing FROM provider WHERE person = 'foo' AND thing = 'bar';
B) SELECT person, place, thing FROM provider WHERE person = 'foo' AND place = 'baz';
C) SELECT person, place, thing FROM provider WHERE person = 'foo' AND place = 'baz' AND thing = 'bar';
D) SELECT per...
C++ Double Address Operator? (&&)
...s. int a, a is an l-value, however (a+2) is an r-value. For example:
void foo(int&& a)
{
//Some magical code...
}
int main()
{
int b;
foo(b); //Error. An rValue reference cannot be pointed to a lValue.
foo(5); //Compiles with no error.
foo(b+3); //Compiles with no error...
Underscore vs Double underscore with variables and methods [duplicate]
...re: when naming a class attribute, invokes name
mangling (inside class FooBar, __boo becomes _FooBar__boo; see below).
__double_leading_and_trailing_underscore__: "magic" objects or
attributes that live in user-controlled namespaces. E.g. __init__,
__import__ or __file__. Never inven...