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How to check if object has any properties in JavaScript?
...5
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/keys
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NSUserDefaults - How to tell if a key exists
...alue is nil:
if([[NSUserDefaults standardUserDefaults] objectForKey:@"YOUR_KEY"] != nil) {
...
}
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AtomicInteger lazySet vs. set
...erve as a soft barrier costing 20 cycles on nehelem intel cpu)
on x86 (x86_64) such a barrier is much cheaper performance-wise than volatile or AtomicLong getAndAdd ,
In an one producer, one consumer queue scenario, xchg soft barrier can force the line of codes before the lazySet(sequence+1) for ...
Uninstall / remove a Homebrew package including all its dependencies
...package names what you don't want to keep installed.
brew leaves > brew_packages
Then you can remove all installed, but unwanted packages and any unnecessary dependencies by running the following command
brew_clean brew_packages
brew_clean is available here: https://gist.github.com/cskeeter...
Fit background image to div
...is the most appropriated one.
Source:
http://www.w3schools.com/cssref/css3_pr_background-size.asp
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DistutilsOptionError: must supply either home or prefix/exec-prefix — not both
...up.cfg file at the root directory of your project, usually where your main __init__.py or executable py file is. So if the root folder of your project is: /path/to/my/project/, create a setup.cfg file in there and put the magic words inside:
[install]
prefix=
OK, now you sould be able to run ...
How do I force a DIV block to extend to the bottom of a page even if it has no content?
...
This site has some excellent examples:
http://www.brunildo.org/test/html_body_0.html
http://www.brunildo.org/test/html_body_11b.html
http://www.brunildo.org/test/index.html
I also recommend going to http://quirksmode.org/
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How to solve the error LNK2019: unresolved external symbol - function?
...l but have not declared that class itself as import/export.
#ifdef MYDLL_EXPORTS
#define DLLEXPORT __declspec(dllexport)
#else
#define DLLEXPORT __declspec(dllimport)
#endif
class DLLEXPORT Book // <--- this class must also be declared as export/import
{
public:
Book();
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Expanding a parent to the height of its children
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such an awesome css value! unsupported in Edge ¯_(ツ)_/¯
– Samer Murad
Jun 3 '19 at 11:49
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How to return a string value from a Bash function
...iable with the string you want to return.
#!/bin/bash
set -x
function pass_back_a_string() {
eval "$1='foo bar rab oof'"
}
return_var=''
pass_back_a_string return_var
echo $return_var
Prints "foo bar rab oof".
Edit: added quoting in the appropriate place to allow whitespace in string to add...