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How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...# modifies z with y's keys and values & returns None
return z
and now:
z = merge_two_dicts(x, y)
In Python 3.9.0a4 or greater (final release date approx October 2020): PEP-584, discussed here, was implemented to further simplify this:
z = x | y # NOTE: 3.9+ ONLY
Explanation
Sa...
What's the difference between JPA and Hibernate? [closed]
...
This metaphor does not add understanding. If you already know the difference, you'll find it amuzing. If you don't know the difference, you will still not know it.
– Nick Volynkin
Feb 15 '17 at 10:18
...
What is the curiously recurring template pattern (CRTP)?
...ss A : public X<A> {...};
It is curiously recurring, isn't it? :)
Now, what does this give you? This actually gives the X template the ability to be a base class for its specializations.
For example, you could make a generic singleton class (simplified version) like this
template <cl...
Eclipse error “ADB server didn't ACK, failed to start daemon”
...sk manager, which has adb.exe process and end (kill) that process
Step 2:
Now, close the eclipse, which is currently running on my computer.
Step 3:
Again, restart eclipse then solved that problem.
For those using OS X
killall adb
For those using Windows
adb kill-server
should do the tric...
Get list of passed arguments in Windows batch script (.bat)
...will be skipped, and also the remainng files.)
– JinSnow
May 2 '17 at 20:36
1
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Convert a list to a data frame
...
Update July 2020:
The default for the parameter stringsAsFactors is now default.stringsAsFactors() which in turn yields FALSE as its default.
Assuming your list of lists is called l:
df <- data.frame(matrix(unlist(l), nrow=length(l), byrow=T))
The above will convert all character columns...
Installing vim with ruby support (+ruby)
...
I think "Compiling Vim With Ruby Integration On Snow Leopard" might actually help. I'm on exactly same boat at the moment.
Ok... got it to work. Took me like half hour or so.
This should help (I got Ubuntu):
sudo apt-get install mercurial
hg clone https://vim.googlecod...
Why is WinRT unmanaged? [closed]
...or is it necessary, given that these languages already support COM.
Right now, the best binding for WinRT is C++ since COM works more efficiently with explicit memory management. With ample help from the new C++ compiler extensions that make it automatic, very similar to _com_ptr_t of old with C++...
Difference between Covariance & Contra-variance
...s T → IE<T>. Notice that this is a "thin arrow".
With me so far?
Now let's consider a relation. There is an assignment compatibility relationship between pairs of types in the first set. A value of type Tiger can be assigned to a variable of type Animal, so these types are said to be "assi...
SQLAlchemy default DateTime
...key=True)
created_date = Column(DateTime, default=datetime.datetime.utcnow)
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