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How to call a Parent Class's method from Child Class in Python?
...P was asking how to do it without explicitly naming the superclass at the call site (Bar, in this case).
– Adam Rosenfield
Apr 30 '09 at 2:13
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Getting the last argument passed to a shell script
$1 is the first argument.
$@ is all of them.
27 Answers
27
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How to delete a file via PHP?
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Check your permissions first of all on the file, to make sure you can a) see it from your script, and b) are able to delete it.
You can also use a path calculated from the directory you're currently running the script in, eg:
unlink(dirname(__FILE__) . "/...
Is there a Python equivalent of the C# null-coalescing operator?
In C# there's a null-coalescing operator (written as ?? ) that allows for easy (short) null checking during assignment:
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Clean code to printf size_t in C++ (or: Nearest equivalent of C99's %z in C++)
...isual C++ for instance use %Iu and %Id respectively, I think that gcc will allow you to use %zu and %zd.
You could create a macro:
#if defined(_MSC_VER) || defined(__MINGW32__) //__MINGW32__ should goes before __GNUC__
#define JL_SIZE_T_SPECIFIER "%Iu"
#define JL_SSIZE_T_SPECIFIER "%Id"
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What does the PHP error message “Notice: Use of undefined constant” mean?
...l_escape_string($_POST['message']);
As is, it was looking for constants called department, name, email, message, etc. When it doesn't find such a constant, PHP (bizarrely) interprets it as a string ('department', etc). Obviously, this can easily break if you do defined such a constant later (tho...
How to check a not-defined variable in JavaScript
...ue for things that don't exist, undefined. The DOM returns null for almost all cases where it fails to find some structure in the document, but in JavaScript itself undefined is the value used.
Second, no, there is not a direct equivalent. If you really want to check for specifically for null, do:
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Could not load file or assembly 'System.Data.SQLite'
I've installed ELMAH 1.1 .Net 3.5 x64 in my ASP.NET project and now I'm getting this error (whenever I try to see any page):
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Checking for empty queryset in Django
...if not my_objects: to demonstrate that this is how they do it in the docs. All else is utterly irrelevant so I do not get your point. They could as well make a thousand queries and it would still be totally irrelevant as this is not the point of this answer, with which I make clear that I agree.
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How to use ELMAH to manually log errors
...log the error in Elmah without causing the application to stop working. It allows for you to catch common exceptions, handle them properly, but still be able to log them.
– PCasagrande
Jan 15 '13 at 19:39
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