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Is returning by rvalue reference more efficient?
...e following
Beta_ab
Beta::toAB() const {
return Beta_ab(1, 1);
}
Now, it's properly moving a temporary Beta_ab object into the return value of the function. If the compiler can, it will avoid the move altogether, by using RVO (return value optimization). Now, you can do the following
Beta...
How can I use if/else in a dictionary comprehension?
...ues_of_key2': {'bar', 'foo'},
'a_not_in_values_of_key3': {'sad', 'so'}}
Now let's suppose you have two dictionaries like this
d1 = {'bad_key1': {'a', 'b', 'c'}, 'bad_key2': {'foo', 'bar'}, 'bad_key3': {'so', 'sad'}}
d2 = {'good_key1': {'foo', 'bar', 'xyz'}, 'good_key2': {'a', 'b', 'c'}}
and yo...
Implementing slicing in __getitem__
...y) and my __getitem__ looks like this:
def __getitem__( self, key ) :
if isinstance( key, slice ) :
#Get the start, stop, and step from the slice
return [self[ii] for ii in xrange(*key.indices(len(self)))]
elif isinstance( key, int ) :
if key < 0 : #Handle negativ...
Python - When to use file vs open
...he moment. They've had a sort of strange relationship, but file() is going now, so there's no need to worry anymore.
The following is from the Python 2.6 docs. [bracket stuff] added by me.
When opening a file, it’s preferable to use open() instead of invoking this [file()] constructor directl...
Explain Morris inorder tree traversal without using stacks or recursion
...sal. So X is made the right child of B, then current is set to Y. The tree now looks like this:
Y
/ \
A B
\
X
/ \
(Y) Z
/ \
C D
(Y) above refers to Y and all of its children, which are omitted for recursion issues. The important part is li...
How to detect reliably Mac OS X, iOS, Linux, Windows in C preprocessor? [duplicate]
If there's some cross-platform C/C++ code that should be compiled on Mac OS X, iOS, Linux, Windows, how can I detect them reliably during preprocessor process?
...
Can you attach Amazon EBS to multiple instances?
...
For anyone else who sees this answer know that Amazon has just released EFS which allows for shared auto-expanding drives that can be mounted over NFS on multiple instances.
– JoshStrange
Apr 9 '15 at 22:02
...
Remove first element from $@ in bash [duplicate]
...
Exactly what I wanted. Now don't need temp variable for dereferencing first argument in "${!1}${@:2}"
– Charlie Gorichanaz
Mar 27 '17 at 22:59
...
iOS app error - Can't add self as subview
I received this crash report, but I don't know how to debug it.
19 Answers
19
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How to do a https request with bad certificate?
...milar but actually completely ignores the certificate check. You need to know that the certificate is valid and signed by a cert that you trust. But in common scenarios, you know that the CN won't match the hostname you connected with. For those, set ServerName on tls.Config. If tls.Config.Serve...