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Is null reference possible?
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Detection of dereferenced null pointers in typeid works based on syntax, instead of based on semantics. That is, if you do typeid(0, *(ostream*)0) you do have undefined behavior - no bad_typeid is guaranteed to be thrown, even though you pass an lvalue resulting from a null pointe...
Unable to generate an explicit migration in entity framework
...processed migration in your application and it requires running Update-Database before you can add another migration.
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Install tkinter for Python
... from sources, but this is usually not the best idea with a binary package-based distro you're apparently running.
It's safer to apt-get install python-tk on your machine(s).
(Works on Debian-derived distributions like for Ubuntu; refer to your package manager and package list on other distribution...
Automatically import modules when entering the python or ipython interpreter
... will allow you to change the startup requirements and other configuration based on a particular case. However, if you'd always like np to be available to you then by all means put it in the startup directory.
For more information on ipython configuration. The docs have a much more complete explana...
Add a column with a default value to an existing table in SQL Server
...raint will not be used and NULL will be inserted as the Value.
Notes were based on everyone's great feedback below.
Special Thanks to:
@Yatrix, @WalterStabosz, @YahooSerious, and @StackMan for their Comments.
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Why do you need explicitly have the “self” argument in a Python method?
...etimes don't.
Python elects to make things like this explicit rather than based on a rule.
Additionally, since nothing is implied or assumed, parts of the implementation are exposed. self.__class__, self.__dict__ and other "internal" structures are available in an obvious way.
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Double Negation in C++
I just came onto a project with a pretty huge code base.
14 Answers
14
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How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...4
>>> min(repeat(lambda: dict(chain(x.items(), y.items()))))
2.740647904574871
>>> min(repeat(lambda: dict(item for d in (x, y) for item in d.items())))
4.266070580109954
$ uname -a
Linux nixos 4.19.113 #1-NixOS SMP Wed Mar 25 07:06:15 UTC 2020 x86_64 GNU/Linux
Resources on Dicti...
JNI converting jstring to char *
...StringUTFChars(javaString, nativeString);
Can fix this errors:
1.error: base operand of '->' has non-pointer type 'JNIEnv {aka _JNIEnv}'
2.error: no matching function for call to '_JNIEnv::GetStringUTFChars(JNIEnv*&, _jstring*&, bool)'
3.error: no matching function for call to '_JNIE...
How do I capture the output of a script if it is being ran by the task scheduler?
...string output of internal Windows environment variables and slices them up based on character position. Because of this, the exact values supplied in the examples below may not be correct for the region of Windows you use. Also, with some regional settings, some components of the date or time may ...