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How to call a parent class function from derived class function?
...uate it by adding the base class's name followed by two colons base_class::foo(...). You should note that unlike Java and C#, C++ does not have a keyword for "the base class" (super or base) since C++ supports multiple inheritance which may lead to ambiguity.
class left {
public:
void foo();
};...
What is a None value?
...n't write the sticker "F", there was already an F sticker on the None, and all you did was move it, from None to "fork". So when you type F = None, you're "reset[ting] it to its original, empty state", if we decided to treat None as meaning empty state.
I can see what he's getting at, but that's a...
python assert with and without parenthesis
...through IDLE. Because assert is a keyword and not a function, you are actually passing in a tuple as the first argument and leaving off the second argument.
Recall that non-empty tuples evaluate to True, and since the assertion message is optional, you've essentially called assert True when you wr...
How to have the cp command create any necessary folders for copying a file to a destination [duplica
... the mkdir/cp command above. It just creates a single level of folder. Actually I'm not sure when it can be useful.
– Penghe Geng
Apr 13 '15 at 14:30
...
Difference between __str__ and __repr__?
...e come right out and say it — I do not believe in debuggers. I don’t really know how to use any debugger, and have never used one seriously. Furthermore, I believe that the big fault in debuggers is their basic nature — most failures I debug happened a long long time ago, in a galaxy far far a...
Add new field to every document in a MongoDB collection
...field" : 1, "test" : "a" }
EDIT:
In case you want to add a new_field to all your collection, you have to use empty selector, and set multi flag to true (last param) to update all the documents
db.your_collection.update(
{},
{ $set: {"new_field": 1} },
false,
true
)
EDIT:
In the above ...
How do I ignore files in a directory in Git?
...
This is actually a copy-paste from the git documentation
– mcont
Aug 17 '18 at 10:00
1
...
Get element inside element by class and ID - JavaScript
...er than worrying about browser compatibility yourself (let someone else do all the work). If you want just a library to do that, then Sizzle will work great. In Sizzle, this would be be done like this:
Sizzle("#foo .bar")[0].innerHTML = "Goodbye world!";
jQuery has the Sizzle library built-in...
Warning: Found conflicts between different versions of the same dependent assembly
...o projects require different versions. You have a few options:
Recompile all projects to use the same versions (e.g. move all to .Net 3.5). This is the preferred option because all code is running with the versions of dependencies they were compiled with.
Add a binding redirect. This will suppress...
How is null + true a string?
...t's walk through this in turn.
X is the null type here - or not a type at all, if you want to think of it that way. It's not providing any candidates. Y is bool, which doesn't provide any user-defined + operators. So the first step finds no user-defined operators.
The compiler then moves on to the...