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Coalesce function for PHP?
...HP 7 introduced a real coalesce operator:
echo $_GET['doesNotExist'] ?? 'fallback'; // prints 'fallback'
If the value before the ?? does not exists or is null the value after the ?? is taken.
The improvement over the mentioned ?: operator is, that the ?? also handles undefined variables without...
Can I save the window layout in Visual Studio 2010/2012/2013?
... and Export Settings Wizard" again to import that settings file, restoring all of your tool windows to their previous layout. (Note that the wizard also allows you to limit what you import from a particular settings file the same way you can limit what you export.)
I use this on my laptop, where sw...
PostgreSQL: Show tables in PostgreSQL
...terface,
First, choose your database
\c database_name
Then, this shows all tables in the current schema:
\dt
Programmatically (or from the psql interface too, of course):
SELECT * FROM pg_catalog.pg_tables;
The system tables live in the pg_catalog database.
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How can I access the MySQL command line with XAMPP for Windows?
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On the Mac, or at least on my Mac using a default install, I accessed it at:
/Applications/xampp/xamppfiles/bin/mysql -uroot -p
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Concatenate a vector of strings/character
... Just a note that if sdata can contain either strings which are all of the same length or of variable lengths then paste(sdata, sep = '', collapse = '') should be used to avoid unexpected results.
– zelanix
Jan 19 '14 at 22:03
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Compiler Ambiguous invocation error - anonymous method and method group with Func or Action
... method group syntax rather than anonymous methods (or lambda syntax) for calling a function.
4 Answers
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How to list all Git tags?
...<pattern>
List tags with names that match the given pattern (or all if no pattern is given).
Typing "git tag" without arguments, also lists all tags.
More recently ("How to sort git tags?", for Git 2.0+)
git tag --sort=<type>
Sort in a specific order.
Supported type...
What are JavaScript's builtin strings?
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First of all, I would like to thank Jason and all the contributors for playing with that funny snippet. I have written that piece of code just for fun in order to send it to my wife on February 14 :) Having only Chrome installed on th...
How to print third column to last column?
... Note that this only works if the delimiter is exactly the same between all columns... For example, you can't use cut with a delimiter like \d+. (That I know of.)
– Zach Wily
Jan 13 '10 at 21:11
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What is the reason why “synchronized” is not allowed in Java 8 interface methods?
...t seem sensible to extend this semantics to default methods as well; after all, they are instance methods with a receiver too. (Note that synchronized methods are entirely a syntactic optimization; they're not needed, they're just more compact than the corresponding synchronized block. There's a r...