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Iterate a list as pair (current, next) in Python
...ometimes need to iterate a list in Python looking at the "current" element and the "next" element. I have, till now, done so with code like:
...
MongoDB: Combine data from multiple collections into one..how?
...you can use as an _id.
For example, let's say you have a users collection and a comments collection and you want to have a new collection that has some user demographic info for each comment.
Let's say the users collection has the following fields:
_id
firstName
lastName
country
gender
age
And...
How does Python 2 compare string and int? Why do lists compare as greater than numbers, and tuples g
...ring for string, numeric ordering for integers).
When you order a numeric and a non-numeric type, the numeric type comes first.
>>> 5 < 'foo'
True
>>> 5 < (1, 2)
True
>>> 5 < {}
True
>>> 5 < [1, 2]
True
When you order two incompatible types where n...
How to redirect to a 404 in Rails?
...
raise ActionController::RoutingError.new('Not Found')
end
Rails also handles AbstractController::ActionNotFound, and ActiveRecord::RecordNotFound the same way.
This does two things better:
1) It uses Rails' built in rescue_from handler to render the 404 page, and
2) it interrupts the executi...
How to extract the first two characters of a string in shell scripting?
...
Probably the most efficient method, if you're using the bash shell (and you appear to be, based on your comments), is to use the sub-string variant of parameter expansion:
pax> long="USCAGol.blah.blah.blah"
pax> short="${long:0:2}" ; echo "${short}"
US
This will set short to be the f...
Multiline strings in JSON
I'm writing some data files in JSON format and would like to have some really long string values split over multiple lines. Using python's JSON module I get a whole lot of errors, whether I use \ or \n as an escape.
...
Functional programming - is immutability expensive? [closed]
...arify some points.
The “in-place” quicksort isn’t really in-place (and quicksort is not by definition in-place). It requires additional storage in the form of stack space for the recursive step, which is in the order of O(log n) in the best case, but O(n) in the worst case.
Implementing a fu...
Can I access constants in settings.py from templates in Django?
...quently-used settings constants to the template such as settings.MEDIA_URL and some of the language settings if you use django's built in generic views or pass in a context instance keyword argument in the render_to_response shortcut function. Here's an example of each case:
from django.shortcuts ...
Install Windows Service created in Visual Studio
...ervice in Visual Studio 2010, I get the message stating to use InstallUtil and net start to run the service.
7 Answers
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Method chaining - why is it a good practice, or not?
... right thing - I had a method which accepted something like 10 parameters, and needed more, but for the most time you only had to specify a few. With overrides this became very cumbersome very fast. Instead I opted for the chaining approach:
MyObject.Start()
.SpecifySomeParameter(asdasd)
.S...