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Does SQLAlchemy have an equivalent of Django's get_or_create?
...t Django's implementation of get_or_create. It checks for integrity error, and relies upon proper use of unique constraints.
– Ivan Virabyan
May 21 '12 at 6:17
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What is the difference between quiet NaN and signaling NaN?
I have read about floating-point and I understand that NaN could result from operations. But I can't understand what these are concepts exactly. What is the difference between them?
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How do I pass a unique_ptr argument to a constructor or a function?
I'm new to move semantics in C++11 and I don't know very well how to handle unique_ptr parameters in constructors or functions. Consider this class referencing itself:
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Is gcc 4.8 or earlier buggy about regular expressions?
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<regex> was implemented and released in GCC 4.9.0.
In your (older) version of GCC, it is not implemented.
That prototype <regex> code was added when all of GCC's C++0x support was highly experimental, tracking early C++0x drafts and being ma...
When would anyone use a union? Is it a remnant from the C-only days?
...pace to work with, or when you're developing an API (or something similar) and you want to force the end user to have only one instance of several objects/types at one time. Are these two guesses even close to right?
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When do I really need to use atomic instead of bool? [duplicate]
...ic by nature" unless it is an std::atomic*-something. That's because the standard says so.
In practice, the actual hardware instructions that are emitted to manipulate an std::atomic<bool> may (or may not) be the same as those for an ordinary bool, but being atomic is a larger concept with wi...
Open file via SSH and Sudo with Emacs
...stion|ssh:you@remotehost:/path RET
Which connects firstly as bird@bastion, and from there to you@remotehost:/path
/su: or /sudo: on remote hosts
You can also use this syntax to sudo/su to root (or of course any other user) on a remote host:
C-xC-f /ssh:you@remotehost|sudo:remotehost:/path/to/file RE...
What is a build tool?
For past 4 years, I have been programming with Eclipse (for Java), and Visual Studio Express (for C#). The IDEs mentioned always seemed to provide every facility a programmer might ask for (related to programming, of course).
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Regex for password must contain at least eight characters, at least one number and both lower and up
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Minimum eight characters, at least one letter and one number:
"^(?=.*[A-Za-z])(?=.*\d)[A-Za-z\d]{8,}$"
Minimum eight characters, at least one letter, one number and one special character:
"^(?=.*[A-Za-z])(?=.*\d)(?=.*[@$!%*#?&])[A-Za-z\d@$!%*#?&]{8,}$"
Mini...
Overloading Macro on Number of Arguments
I have two macros FOO2 and FOO3 :
8 Answers
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