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Should you always favor xrange() over range()?
...might prefer range():
In python 3, range() does what xrange() used to do and xrange() does not exist. If you want to write code that will run on both Python 2 and Python 3, you can't use xrange().
range() can actually be faster in some cases - eg. if iterating over the same sequence multiple time...
Getting started with Haskell
... to stick.
Now, in learning various imperative/OO languages (like C, Java, PHP), exercises have been a good way for me to go. But since I don't really know what Haskell is capable of and because there are many new concepts to utilize, I haven't known where to start.
...
How do you run a Python script as a service in Windows?
...e which provides a higher level interface for operations on these objects, and the other programs to access the objects through that service.
...
What's a good way to extend Error in JavaScript?
I want to throw some things in my JS code and I want them to be instanceof Error, but I also want to have them be something else.
...
Removing event listener which was added with bind
...
Although what @machineghost said was true, that events are added and removed the same way, the missing part of the equation was this:
A new function reference is created after .bind() is called!
See Does bind() change the function reference? | How to set permanently?
So, to add or r...
How to access the ith column of a NumPy multidimensional array?
... reference is reflected in the original array.
– harmands
Oct 18 '16 at 14:21
add a comment
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How to get the original value of an attribute in Rails
...ibute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in rails 5.1, now you should append _before_last_save
Something like:
before_save object
do_something_with object.name_...
How to import a module given the full path?
...rom_spec(spec)
spec.loader.exec_module(foo)
foo.MyClass()
For Python 3.3 and 3.4 use:
from importlib.machinery import SourceFileLoader
foo = SourceFileLoader("module.name", "/path/to/file.py").load_module()
foo.MyClass()
(Although this has been deprecated in Python 3.4.)
For Python 2 use:
im...
Is there a foreach loop in Go?
...h entry it assigns iteration values to corresponding iteration
variables and then executes the block.
As an example:
for index, element := range someSlice {
// index is the index where we are
// element is the element from someSlice for where we are
}
If you don't care about the index...
How to check if a python module exists without importing it
... After a year I came across the same problem I mentioned just above and was digging for a solution for Python 2: pkgutil.find_loader("my.package.module") returns a loader if the package/module exists and None if not. Please update your answer for Python 2, as masking the ImportError drove me ...