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Alphabet range in Python
...gt;>> string.ascii_lowercase
'abcdefghijklmnopqrstuvwxyz'
If you really need a list:
>>> list(string.ascii_lowercase)
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
And to do it with range
>&g...
What is the curiously recurring template pattern (CRTP)?
... 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 <class ActualClass>
class Singleton
{
...
What's the difference between NOT EXISTS vs. NOT IN vs. LEFT JOIN WHERE IS NULL?
...ot slower. On the other hand, a join may also perform badly if there is no index that can be used, so just because you use a join doesn't mean that you are safe. You would have to examine the execution plan of the query to tell if there may be any performance problems.
...
Generate random numbers using C++11 random library
... functions and why not to use rand(). In it, he included a slide that basically solves your question. I've copied the code from that slide below.
You can see his full talk here: http://channel9.msdn.com/Events/GoingNative/2013/rand-Considered-Harmful
#include <random>
#include <iostream&g...
What are valid values for the id attribute in HTML?
...
For HTML 4, the answer is technically:
ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").
HTML 5 is even more permissiv...
Custom thread pool in Java 8 parallel stream
Is it possible to specify a custom thread pool for Java 8 parallel stream ? I can not find it anywhere.
15 Answers
...
Regular Expression: Any character that is NOT a letter or number
...
@sbmaxx I want to replace all except &, (, ) these characters. how could i add this condition in the current regex.
– K Pal
Feb 21 '19 at 11:24
...
When using Spring Security, what is the proper way to obtain current username (i.e. SecurityContext)
...ntroller" class="com.foo.FooController">
...
<constructor-arg index="1">
<bean class="com.foo.SecurityContextHolderFacade">
</constructor-arg>
</bean>
It seems more than a little silly that Spring, a dependency injection container of all things, has not supp...
How would I create a UIAlertView in Swift?
... the handler might need to pass the chosen title off to some other method call
– Honey
Nov 30 '16 at 17:27
...
Python: Checking if a 'Dictionary' is empty doesn't seem to work
...; not dct
True
>>>
Thus, your isEmpty function is unnecessary. All you need to do is:
def onMessage(self, socket, message):
if not self.users:
socket.send("Nobody is online, please use REGISTER command" \
" in order to register into the server")
else:...
