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What is the difference between include and extend in Ruby?
...correct. However there is more to it than that.
If you have a class Klazz and module Mod, including Mod in Klazz gives instances of Klazz access to Mod's methods. Or you can extend Klazz with Mod giving the class Klazz access to Mod's methods. But also you can extend an arbitrary object with o.exte...
How do I parse XML in Python?
I have many rows in a database that contains XML and I'm trying to write a Python script to count instances of a particular node attribute.
...
How to convert JSON data into a Python object
...
UPDATE
With Python3, you can do it in one line, using SimpleNamespace and object_hook:
import json
from types import SimpleNamespace
data = '{"name": "John Smith", "hometown": {"name": "New York", "id": 123}}'
# Parse JSON into an object with attributes corresponding to dict keys.
x = json.lo...
How to check if a process id (PID) exists
...will have a race condition.
If you want to ignore the text output of kill and do something based on the exit code, you can
if ! kill $pid > /dev/null 2>&1; then
echo "Could not send SIGTERM to process $pid" >&2
fi
...
Explanation of BASE terminology
...e system unavailable (or inconsistent). So you can see that 'availability' and 'partition tolerance' go hand in hand. There's more detail on this in this article.
– Niels van der Rest
Apr 14 '14 at 18:29
...
promise already under evaluation: recursive default argument reference or earlier problems?
...1, f..=f){ g.(1,T, f.=f..) }? In cases with more recursions, is it a good and safe practice adding more .? (2) if f is a non-function argument, for example g <- function(x, T, f=f){ exp(-fx/T) }* and test<- function(g.=g, T=1, f=f){ g.(1,T, f=f.) }, will using the same name for both formal a...
could not resolve host github.com error while cloning remote repository in git
What I did: I have created a remote repository on Github and I am trying to clone the remote repository on my local machine. While cloning I am providing the clone URL & target folder.
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How to check if a float value is a whole number
...ke into account that in Python 2, 1/3 is 0 (floor division for integer operands!), and that floating point arithmetic can be imprecise (a float is an approximation using binary fractions, not a precise real number). But adjusting your loop a little this gives:
>>> for n in range(12000, -1,...
Is .NET Remoting really deprecated?
...at is. I haven't seen any official word that Remoting is being deprecated, and it seems to me there are certainly scenarios where Remoting makes more sense than WCF. None of the Remoting-related objects or methods have been deprecated, even in version 4.0 of the framework. It is also my understandin...
How to correctly use the extern keyword in C
...keyword, the function / variable is assumed to be available somewhere else and the resolving is deferred to the linker.
There's a difference between "extern" on functions and on variables: on variables it doesn't instantiate the variable itself, i.e. doesn't allocate any memory. This needs to be do...