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How do I use boolean variables in Perl?
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In Perl, the following evaluate to false in conditionals:
0
'0'
undef
'' # Empty scalar
() # Empty list
('')
The rest are true. There are no barewords for true or false.
share
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How to Sort Multi-dimensional Array by Value?
...unction($a, $b) {
return $a['order'] - $b['order'];
});
And finally with PHP 7 you can use the spaceship operator:
usort($myArray, function($a, $b) {
return $a['order'] <=> $b['order'];
});
To extend this to multi-dimensional sorting, reference the second/third sorting elements if...
Disabling Chrome cache for website development
I am modifying a site's appearance (CSS modifications) but can't see the result on Chrome because of annoying persistent cache. I tried Shift +refresh but it doesn't work.
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Can't start Eclipse - Java was started but returned exit code=13
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There are working combinations of OS, JDK and Eclipse bitness. In my case, I was using a 64-bit JDK with a 32-bit Eclipse on a 64-bit OS. After downgrading the JDK to 32-bit, Eclipse started working.
Use one of the following combinations.
32-bit OS, 32-bit JDK, 32-bit Eclipse ...
How to stop Jenkins installed on Mac Snow Leopard?
I have installed Jenkins executable on OSX, but now I want to stop it running. Whenever I kill it, no matter how, it just restarts immediately.
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Change URL and redirect using jQuery
...eed jQuery to do this; you can just use the standard properties.
However, it seems you don't seem to know the difference between window.location.replace(url) and window.location = url.
window.location.replace(url) replaces the current location in the address bar by a new one. The page that was ca...
Is it possible to roll back CREATE TABLE and ALTER TABLE statements in major SQL databases?
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http://wiki.postgresql.org/wiki/Transactional_DDL_in_PostgreSQL:_A_Competitive_Analysis provides an overview of this issue from PostgreSQL's perspective.
Is DDL transactional according to this document?
PostgreSQL - yes
MySQL - no; DDL causes an implicit commit
Oracle Database 11g Release 2 and...
Unable to find specific subclass of NSManagedObject
I'm working on developing an app with Core Data. When I created an instance using:
13 Answers
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Is there a way to break a list into columns?
My webpage has a 'skinny' list: for example, a list of 100 items of one word in length each. To reduce scrolling, I want to present this list in two or even four columns on the page. How should I do this with CSS?
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How do I convert an existing callback API to promises?
I want to work with promises but I have a callback API in a format like:
20 Answers
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