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`static` keyword inside function?
...$has_run in your example) between multiple calls.
You could use this for different purposes, for example:
function doStuff() {
static $cache = null;
if ($cache === null) {
$cache = '%heavy database stuff or something%';
}
// code using $cache
}
In this example, the if would only b...
Javascript - remove an array item by value [duplicate]
...,3,56,6,8,90],
id_tag = 90,
position = tag_story.indexOf(id_tag);
if ( ~position ) tag_story.splice(position, 1);
P.S. For an explanation of that cool ~ tilde shortcut, see this post:
Using a ~ tilde with indexOf to check for the existence of an item in an array.
Note: IE < 9 does ...
Convert data.frame columns from factors to characters
...
Just following on Matt and Dirk. If you want to recreate your existing data frame without changing the global option, you can recreate it with an apply statement:
bob <- data.frame(lapply(bob, as.character), stringsAsFactors=FALSE)
This will convert al...
Stopping scripters from slamming your website
...
How about implementing something like SO does with the CAPTCHAs?
If you're using the site normally, you'll probably never see one. If you happen to reload the same page too often, post successive comments too quickly, or something else that triggers an alarm, make them prove they're human....
jQuery click events firing multiple times
...ck handler ain't a one-off throwaway thing. Especially when it's the bulky if-if-if shown in the question. You're supposed to attach it and let it do its work as long as the page lives.
– Marco Faustinelli
Jun 19 '15 at 5:44
...
Remove redundant paths from $PATH variable
...in:/usr/bin:/sbin:/bin:/usr/games
that would be for the current session, if you want to change permanently add it to any .bashrc, bash.bashrc, /etc/profile - whatever fits your system and user needs.
Note: This is for Linux. We'll make this clear for new coders. (` , ') Don't try to SET = these.
...
AngularJS : automatically detect change in model
...()es for you behind the scenes.
By default $watch compares by reference. If you set the third parameter to $watch to true, Angular will instead "shallow" watch the object for changes. For arrays this means comparing the array items, for object maps this means watching the properties. So this sho...
When writing a directive in AngularJS, how do I decide if I need no new scope, a new child scope, or
...no new scope at all
I don't use this very often, but as @MarkRajcok said, if the directive doesn't access any scope variables (and obviously doesn't set any!) then this is just fine as far as I am concerned. This is also helpful for child directives that are only used in the context of the parent d...
Scale Image to fill ImageView width and keep aspect ratio
...up/down-scale as needed keeping aspect ratio.
scaleType="centerInside"
if the intrinsic width of src is smaller than parent widthwill center the image horizontally
if the intrinsic width of src is larger than parent widthwill make it as wide as the parent allows and down-scale keeping aspect ra...
How to generate a core dump in Linux on a segmentation fault?
...
This depends on what shell you are using. If you are using bash, then the ulimit command controls several settings relating to program execution, such as whether you should dump core. If you type
ulimit -c unlimited
then that will tell bash that its programs can ...