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val-mutable versus var-immutable in Scala
...that means is that, if I have an expression "e", I could make a val x = e, and replace e with x. This is the property that mutability break. Whenever you need to make a design decision, maximize for referential transparency.
As a practical matter, a method-local var is the safest var that exists, s...
Access an arbitrary element in a dictionary in Python
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On Python 3, non-destructively and iteratively:
next(iter(mydict.values()))
On Python 2, non-destructively and iteratively:
mydict.itervalues().next()
If you want it to work in both Python 2 and 3, you can use the six package:
six.next(six.itervalue...
Are C++ enums signed or unsigned?
Are C++ enums signed or unsigned? And by extension is it safe to validate an input by checking that it is = your min value (assuming you started at 0 and incremented by 1)?
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How can I have ruby logger log output to stdout as well as file?
...ime Logger calls puts on your MultiIO object, it will write to both STDOUT and your log file.
Edit: I went ahead and figured out the rest of the interface. A log device must respond to write and close (not puts). As long as MultiIO responds to those and proxies them to the real IO objects, this s...
How is std::function implemented?
...ed by the compiler creating a class with overloaded function call operator and the referenced variables as members. This suggests that the size of lambda expressions varies, and given enough references variables that size can be arbitrarily large .
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Python Process Pool non-daemonic?
...s creates the worker processes in its __init__ method, makes them daemonic and starts them, and it is not possible to re-set their daemon attribute to False before they are started (and afterwards it's not allowed anymore). But you can create your own sub-class of multiprocesing.pool.Pool (multiproc...
Python threading.timer - repeat function every 'n' seconds
I want to fire off a function every 0.5 seconds and be able to start and stop and reset the timer. I'm not too knowledgeable of how Python threads work and am having difficulties with the python timer.
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Given a URL to a text file, what is the simplest way to read the contents of the text file?
...xt file, what is the simplest way to access the contents off the text file and print the contents of the file out locally line-by-line without saving a local copy of the text file?
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How to identify all stored procedures referring a particular table
I created a table on development environment for testing purpose and there are few sp's which are refreing this table. Now I have have to drop this table as well as identify all sp's which are referring this table. I am facing difficulty to find list of all sp's. Please suggest some query by assumin...
Decorators with parameters?
...ecorator with arguments should return a function that will take a function and return another function. So it should really return a normal decorator. A bit confusing, right? What I mean is:
def decorator_factory(argument):
def decorator(function):
def wrapper(*args, **kwargs):
...