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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 ...
Program only crashes as release build — how to debug?
I've got a "Schroedinger's Cat" type of problem here -- my program (actually the test suite for my program, but a program nonetheless) is crashing, but only when built in release mode, and only when launched from the command line. Through caveman debugging (ie, nasty printf() messages all over the ...
How do I enable EF migrations for multiple contexts to separate databases?
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The 2nd call to Enable-Migrations is failing because the Configuration.cs file already exists. If you rename that class and file, you should be able to run that 2nd Enable-Migrations, which will create another Configuration.cs.
You ...
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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Pretty print in MongoDB shell as default
...y, everything is output to a single line and it's difficult to read, especially with nested arrays and documents.
8 Answers...
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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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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What is __gxx_personality_v0 for?
... quick grep of the libstd++ code base revealed the following two usages of __gx_personality_v0:
In libsupc++/unwind-cxx.h
// GNU C++ personality routine, Version 0.
extern "C" _Unwind_Reason_Code __gxx_personality_v0
(int, _Unwind_Action, _Unwind_Exceptio...
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...