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Python: changing value in a tuple
...'m new to python so this question might be a little basic. I have a tuple called values which contains the following:
17 ...
What's wrong with nullable columns in composite primary keys?
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Primary keys are for uniquely identifying rows. This is done by comparing all parts of a key to the input.
Per definition, NULL cannot be part of a successful comparison. Even a comparison to itself (NULL = NULL) will fail. This means a key containing NULL would not work.
Additonally, NULL is al...
Determine if string is in list in JavaScript
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You can call indexOf:
if (['a', 'b', 'c'].indexOf(str) >= 0) {
//do something
}
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AngularJS. How to call controller function from outside of controller component
How I can call function defined under controller from any place of web page (outside of controller component)?
10 Answers
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How do I pass a method as a parameter in Python
...thodToRun()
return result
obj.method2(obj.method1)
Note: I believe a __call__() method does exist, i.e. you could technically do methodToRun.__call__(), but you probably should never do so explicitly. __call__() is meant to be implemented, not to be invoked from your own code.
If you wanted me...
SQL - using alias in Group By
...ceptions though: MySQL and Postgres seem to have additional smartness that allows it.
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Listen for key press in .NET console app
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Use Console.KeyAvailable so that you only call ReadKey when you know it won't block:
Console.WriteLine("Press ESC to stop");
do {
while (! Console.KeyAvailable) {
// Do something
}
} while (Console.ReadKey(true).Key != ConsoleKey.Escape);
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Python concatenate text files
...new file. I could open each file by f = open(...) , read line by line by calling f.readline() , and write each line into that new file. It doesn't seem very "elegant" to me, especially the part where I have to read//write line by line.
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Why is early return slower than else?
...e a theory for you.
I tried your code and get the same of results, without_else() is repeatedly slightly slower than with_else():
>>> T(lambda : without_else()).repeat()
[0.42015745017874906, 0.3188967452567226, 0.31984281521812363]
>>> T(lambda : with_else()).repeat()
[0.3600984...
Resharper- Find all unused classes
...g the "Find Usages" option. Is there any way I can see or get the list of all the unused classes or files in my project ?
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