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Performance difference for control structures 'for' and 'foreach' in C#
...t will depend on whether you're doing any real work in the loop. In almost all cases, the difference to performance won't be significant, but the difference to readability favours the foreach loop.
I'd personally use LINQ to avoid the "if" too:
foreach (var item in list.Where(condition))
{
}
EDI...
Get the latest record from mongodb collection
...1 means order opposite of the one that records are inserted in.
Edit: For all the downvoters, above is a Mongoose syntax,
mongo CLI syntax is: db.collectionName.find({}).sort({$natural:-1}).limit(1)
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PHP “php://input” vs $_POST
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The reason is that php://input returns all the raw data after the HTTP-headers of the request, regardless of the content type.
The PHP superglobal $_POST, only is supposed to wrap data that is either
application/x-www-form-urlencoded (standard content type for...
How do I profile memory usage in Python?
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This one has been answered already here: Python memory profiler
Basically you do something like that (cited from Guppy-PE):
>>> from guppy import hpy; h=hpy()
>>> h.heap()
Partition of a set of 48477 objects. Total size = 3265516 bytes.
Index Count % Size % Cumulat...
Logging uncaught exceptions in Python
... global type (much like using var self = this in Javascript). It doesn't really matter unless you need to access the type object inside your function, in which case you can use type_ as the argument instead.
– Ryan P
Jan 2 '13 at 17:08
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How to get all registered routes in Express?
... web application built using Node.js and Express. Now I would like to list all registered routes with their appropriate methods.
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How to len(generator()) [duplicate]
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Generators have no length, they aren't collections after all.
Generators are functions with a internal state (and fancy syntax). You can repeatedly call them to get a sequence of values, so you can use them in loop. But they don't contain any elements, so asking for the length of ...
How to implement a good __hash__ function in python [duplicate]
... are equal. It also shouldn't change over the lifetime of the object; generally you only implement it for immutable objects.
A trivial implementation would be to just return 0. This is always correct, but performs badly.
Your solution, returning the hash of a tuple of properties, is good. But note...
log messages appearing twice with Python Logging
I'm using Python logging, and for some reason, all of my messages are appearing twice.
8 Answers
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Elegant Python function to convert CamelCase to snake_case?
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name = pattern.sub('_', name).lower()
To handle more advanced cases specially (this is not reversible anymore):
def camel_to_snake(name):
name = re.sub('(.)([A-Z][a-z]+)', r'\1_\2', name)
return re.sub('([a-z0-9])([A-Z])', r'\1_\2', name).lower()
print(camel_to_snake('camel2_camel2_case')) #...