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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...
jQuery get value of selected radio button
...use you when you're used to seeing "" as the default value via the .val() call.
– xji
Jan 8 '18 at 22:30
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Name node is in safe mode. Not able to leave
...e leave
hadoop dfsadmin has been deprecated and so is hadoop fs command, all hdfs related tasks are being moved to a separate command hdfs.
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How do I print to the debug output window in a Win32 app?
...you can use the L prefix:
OutputDebugStringW(L"My output string.");
Normally you will use the macro version together with the _T macro like this:
OutputDebugString(_T("My output string."));
If you project is configured to build for UNICODE it will expand into:
OutputDebugStringW(L"My output s...
SQLAlchemy: print the actual query
I'd really like to be able to print out valid SQL for my application, including values, rather than bind parameters, but it's not obvious how to do this in SQLAlchemy (by design, I'm fairly sure).
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How can I manually generate a .pyc file from a .py file
...n not depend on Python's "import" statement to generate .pyc file automatically
8 Answers
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Combining two expressions (Expression)
...m);
}
Starting from .NET 4.0, there is the ExpressionVisitor class which allows you to build expressions that are EF safe.
public static Expression<Func<T, bool>> AndAlso<T>(
this Expression<Func<T, bool>> expr1,
Expression<Func<T, bool>&...
How do I access the request object or any other variable in a form's clean() method?
... but how can I access the request object? Can I modify the clean method to allow variables input?
11 Answers
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C# binary literals
... @Dai that’s no different than hex literals. In other words, all constants are big endian, but stored little endian on Intel/AMD and most ARMs. 0xDEADBEEF will be stored as 0xEF 0xBE 0xAD 0xDE
– Cole Johnson
Sep 2 '19 at 18:28
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Forward an invocation of a variadic function in C
... - is there a solution how to fix it? (MSVC prints: too few arguments for call)
– mvorisek
Jul 20 at 17:28
@mvorisek: ...