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When to use Comparable and Comparator
...e sorting was an unusual use of the class, or the sorting only makes sense for a specific use case, then a Comparator is a better option.
Put another way, given the class name, is it clear how a comparable would sort, or do you have to resort to reading the javadoc? If it is the latter, odds are ev...
How to modify a global variable within a function in bash?
...unc() {
echo "Hello"
}
var="$(myfunc)"
echo "$var"
Gives:
Hello
For a numerical value from 0-255, you can use return to pass the number as the exit status:
mysecondfunc() {
echo "Hello"
return 4
}
var="$(mysecondfunc)"
num_var=$?
echo "$var - num is $num_var"
Gives:
Hello - ...
Convert a String In C++ To Upper Case
...
This appears to perform extremely badly with g++ 5.2 -O3, and Boost 1.58 (like 30x worse than calling glibc's toupper in a loop.) There's a dynamic_cast of the locale that doesn't get hoisted out of the per-char loop. See my answer. On the p...
Calling class staticmethod within the class body?
...2E3CBA8>
>>> dir(z)
['__class__', '__delattr__', '__doc__', '__format__', '__func__', '__get__', '__getattribute__', '__hash__', '__init__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__']
>>> z.__func__
<funct...
Why do people use __(double underscore) so much in C++
...dations :
The use of two underscores (`__') in identifiers is reserved for the compiler's internal use according to the ANSI-C standard.
Underscores (`_') are often used in names of library functions (such as "_main" and "_exit"). In order to avoid collisions, do not begin an identifier wit...
Can I redirect the stdout in python into some sort of string buffer?
...
I think there is no need to add try/finally block for this solution.
– snr
Jul 16 '18 at 14:50
add a comment
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How to add property to a class dynamically?
...a thing called a descriptor. It's an object that provides custom handling for a given attribute, on a given class. Kinda like a way to factor a huge if tree out of __getattribute__.
When I ask for foo.b in the example above, Python sees that the b defined on the class implements the descriptor pr...
How to get a reference to a module inside the module itself?
...
except for this won't be quite correct if module is reloaded; I don't think there's any place where a reference is guaranteed to be kept, if there was, reloading wouldn't really work, right?
– Dima Tisnek
...
How do you do a limit query in JPQL or HQL?
...
This was posted on the Hibernate forum a few years back when asked about why this worked in Hibernate 2 but not in Hibernate 3:
Limit was never a supported clause
in HQL. You are meant to use
setMaxResults().
So if it worked in Hibernate 2, it seem...
Run function from the command line
...
For some reason, this didn't work for me, while replacing print foo.hello() with print(foo.hello()) did. I don't have the python knowledge to explain why this is, so if someone else could explain what can be going on, that wo...