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'typeid' versus 'typeof' in C++
...ns type identification information at run time. It basically returns a type_info object, which is equality-comparable with other type_info objects.
Note, that the only defined property of the returned type_info object has is its being equality- and non-equality-comparable, i.e. type_info objects de...
Manipulate a url string by adding GET parameters
...
Basic method
$query = parse_url($url, PHP_URL_QUERY);
// Returns a string if the URL has parameters or NULL if not
if ($query) {
$url .= '&category=1';
} else {
$url .= '?category=1';
}
More advanced
$url = 'http://example.com/search?ke...
Order discrete x scale by frequency/value
...library(ggplot2)
# Automatic levels
ggplot(mtcars, aes(factor(cyl))) + geom_bar()
# Manual levels
cyl_table <- table(mtcars$cyl)
cyl_levels <- names(cyl_table)[order(cyl_table)]
mtcars$cyl2 <- factor(mtcars$cyl, levels = cyl_levels)
# Just to be clear, the above line is no different...
Argparse: Way to include default values in '--help'?
...parser = argparse.ArgumentParser(
# ... other options ...
formatter_class=argparse.ArgumentDefaultsHelpFormatter)
To quote the documentation:
The other formatter class available, ArgumentDefaultsHelpFormatter, will add information about the default value of each of the arguments.
Not...
What underlies this JavaScript idiom: var self = this?
...
I usually use _this
– djheru
Mar 20 '14 at 19:48
6
...
Auto Resize Image in CSS FlexBox Layout and keeping Aspect Ratio?
...values for align-items you could use to override: w3schools.com/cssref/css3_pr_align-items.asp
– Kyle Vassella
Oct 31 '17 at 16:50
...
Knight's Shortest Path on Chessboard
...oints in a graph can be found using http://en.wikipedia.org/wiki/Dijkstra's_algorithm
Pseudo-code from wikipedia-page:
function Dijkstra(Graph, source):
for each vertex v in Graph: // Initializations
dist[v] := infinity // Unknown distance function from source to ...
Golang production web application configuration
... timeout server 50000
frontend http
bind :80
acl is_stats hdr(host) -i hastats.myapp.com
use_backend stats if is_stats
default_backend myapp
capture request header Host len 20
capture request h...
Null vs. False vs. 0 in PHP
...ity a function can return false for non existent values (e.g. strpos, input_filter) and null for failure (e.g. input_filter). so the answer is, use ===false and/or ===null, after reading that particular function documentation.
– gcb
Apr 18 '11 at 9:33
...
PHP Fatal error: Using $this when not in object context
...it is still wrong. You can call an instance method with ::. It is against E_STRICT, but it does work as long as the method body does not reference the instance scope, e.g. uses $this. Also, self::foo will not point to $this->foo. It references a class constant. Both, self::foo and self::$foo woul...