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What does 'const static' mean in C and C++?
I saw this in some code here on StackOverflow and I couldn't figure out what it does. Then I saw some confused answers on other forums. My best guess is that it's used in C to hide the constant foo from other modules. Is this correct? If so, why would anyone use it in a C++ context where you can j...
MySQL case insensitive select
...? And if not, what query would I have to send so that I can do something like:
14 Answers
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Swift - class method which must be overridden by subclass
Is there a standard way to make a "pure virtual function" in Swift, ie. one that must be overridden by every subclass, and which, if it is not, causes a compile time error?
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What is href=“#” and why is it used?
On many websites I see links that have href="#" . What does it mean? What is it used for?
9 Answers
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What does !important mean in CSS?
...ave priority.
Using !important has its purposes (though I struggle to think of them), but it's much like using a nuclear explosion to stop the foxes killing your chickens; yes, the foxes will be killed, but so will the chickens. And the neighbourhood.
It also makes debugging your CSS a nightmare (...
What is the difference between JOIN and UNION?
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UNION puts lines from queries after each other, while JOIN makes a cartesian product and subsets it -- completely different operations. Trivial example of UNION:
mysql> SELECT 23 AS bah
-> UNION
-> SELECT 45 AS bah;
+-----+
| bah |
+-----+
| 23 |
| 45 |
+-----+
2 ...
How to initialize a dict with keys from a list and empty value in Python?
I'd like to get from this:
6 Answers
6
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Get first n characters of a string
...tring = substr($string,0,10).'...';
Update:
Based on suggestion for checking length (and also ensuring similar lengths on trimmed and untrimmed strings):
$string = (strlen($string) > 13) ? substr($string,0,10).'...' : $string;
So you will get a string of max 13 characters; either 13 (or les...
How do I change the working directory in Python?
cd is the shell command to change the working directory.
14 Answers
14
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The 'json' native gem requires installed build tools
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I believe those installers make changes to the path. Did you try closing and re-opening the CMD window after running them and before the last attempt to install the gem that wants devkit present?
Also, be sure you are using the right devkit installer ...