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What is an abstract class in PHP?
...re interface. Also interfaces are a special case of abstract classes where ALL methods are abstract.
See this section of the PHP manual for further reference.
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Find object by id in an array of JavaScript objects
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Basically I always use === because it works exactly like == in other programming languages. I consider == to be non-existent in JavaScript.
– Vicky Chijwani
Dec 11 '12 at 13:27
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javascript: pause setTimeout();
...imilar to what you were suggesting in the question:
var Timer = function(callback, delay) {
var timerId, start, remaining = delay;
this.pause = function() {
window.clearTimeout(timerId);
remaining -= Date.now() - start;
};
this.resume = function() {
start =...
What's the difference between echo, print, and print_r in PHP?
...s, although such usage is rare; echo is slightly faster than print. (Personally, I always use echo, never print.)
var_dump prints out a detailed dump of a variable, including its type and the type of any sub-items (if it's an array or an object). print_r prints a variable in a more human-readable f...
What does the caret operator (^) in Python do?
...his way:
1000 # 8 (binary)
0011 # 3 (binary)
---- # APPLY XOR ('vertically')
1011 # result = 11 (binary)
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PostgreSQL Autoincrement
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Yes, SERIAL is the equivalent function.
CREATE TABLE foo (
id SERIAL,
bar varchar);
INSERT INTO foo (bar) values ('blah');
INSERT INTO foo (bar) values ('blah');
SELECT * FROM foo;
1,blah
2,blah
SERIAL is just a create table time macro around sequences. You can not alter ...
Why is parenthesis in print voluntary in Python 2.7?
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In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
What exactly does an #if 0 … #endif block do?
...h one important difference: Nesting is not a problem. Consider this code:
foo();
bar(x, y); /* x must not be NULL */
baz();
If I want to comment it out, I might try:
/*
foo();
bar(x, y); /* x must not be NULL */
baz();
*/
Bzzt. Syntax error! Why? Because block comments do not nest, and so (as ...
Naming cookies - best practices [closed]
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@Emanuil: To distinguish it from all the other cookies generated by other apps on the same domain.
– Ignacio Vazquez-Abrams
Sep 19 '12 at 20:50
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Include constant in string without concatenating
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Yes it is (in some way ;) ):
define('FOO', 'bar');
$test_string = sprintf('This is a %s test string', FOO);
This is probably not what you were aiming for, but I think, technically this is not concatenation but a substitution and from this assumption, it inclu...