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What is a NullReferenceException, and how do I fix it?
.... This means you either set it to null, or you never set it to anything at all.
Like anything else, null gets passed around. If it is null in method "A", it could be that method "B" passed a null to method "A".
null can have different meanings:
Object variables which are uninitialized and hence poi...
Fast Linux File Count for a large number of files
...ke a while if there are a lot of them. Also there will be no output until all of the names are read and sorted. Use the ls -f option to turn off sorting.
ls -f | wc -l
Note that this will also enable -a, so ., .., and other files starting with . will be counted.
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Getting a random value from a JavaScript array
... @SapphireSun this is correct. Note the Math.floor(Math.random(...)) call, which rounds down.
– ashes999
Jan 19 '14 at 12:43
34
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Delete multiple objects in django
...sing a webpage. There is no category to select from so I can't delete from all of them like that. Do I have to implement my own delete form and process it in django or does django have a way to already do this? As its implemented in the admin interface.
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Why does Python code use len() function instead of a length method?
...on objects which have a length and use the built-in len() function, which calls it for you, similar to the way you would implement __iter__() and use the built-in iter() function (or have the method called behind the scenes for you) on objects which are iterable.
See Emulating container types for m...
Requirejs domReady plugin vs Jquery $(document).ready()?
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It seems like all the key points were already hit, but a few details fell through the cracks. Mainly:
domReady
It is both a plugin and a module. If you include it in the the requirements array w/ a trailing ! your module won't execute un...
How to list variables declared in script in bash?
... I have to make something to save them to file.
My question is how to list all variables declared in my script and get list like this:
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What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
... platforms, memory leaks are often caused by unreleased pointers. Traditionally, it has always been of utmost importance to check your allocs, copies and retains to make sure each has a corresponding release message.
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What is the use for Task.FromResult in C#
In C# and TPL ( Task Parallel Library ), the Task class represents an ongoing work that produces a value of type T.
6 Ans...
How can you profile a Python script?
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Python includes a profiler called cProfile. It not only gives the total running time, but also times each function separately, and tells you how many times each function was called, making it easy to determine where you should make optimizations.
You c...