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What is the purpose of Flask's context stacks?
...backend". In other words, the Flask(...) application constructor has been called twice, creating two instances of a Flask application.
Contexts
When you are working with Flask, you often end up using global variables to access various functionality. For example, you probably have code that reads.....
How to check if variable is string with python 2 and 3 compatibility
...
What about this, works in all cases?
isinstance(x, ("".__class__, u"".__class__))
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After Installing Java JDK 7 For Mac OS X - mvn -version still shows java version 1.6.0_31
Oracle released Java JDK 7 on April 26 for Mac OS X. I followed the install instructions and when I do java -version in a terminal window I get:
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Dealing with float precision in Javascript [duplicate]
...of significant digits, like this:
(Math.floor(y/x) * x).toFixed(2)
Convert all your numbers to integers
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What is the difference between old style and new style classes in Python?
...(x) is always <type
'instance'>.
This reflects the fact that all old-style instances, independently of
their class, are implemented with a single built-in type, called
instance.
New-style classes were introduced in Python 2.2 to unify the concepts of class and type.
A new-s...
Find object in list that has attribute equal to some value (that meets any condition)
...eat solution, but how do i modify your line so that I can make x.value actually mean x.fieldMemberName where that name is stored in value? field = "name" next((x for x in test_list if x.field == value), None) so that in this case, i am actually checking against x.name, not x.field
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Polymorphism in C++
...ecific code selected?
Run time means the compiler must generate code for all the types the program might handle while running, and at run-time the correct code is selected (virtual dispatch)
Compile time means the choice of type-specific code is made during compilation. A consequence of this: say...
What is the most efficient string concatenation method in python?
... idiomatic and thus easier for other python programmers to understand.
Finally, the golden rule of optimization: don't optimize unless you know you need to, and measure rather than guessing.
You can measure different methods using the timeit module. That can tell you which is fastest, instead of r...
Are list-comprehensions and functional functions faster than “for loops”?
...ike map() , filter() and reduce() faster than a for loop? Why, technically, they run in a C speed , while the for loop runs in the python virtual machine speed ?.
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How to check that an element is in a std::set?
... Note that using count() instead of find() is never better but potentially worse. This is because find() will return after the first match, count() will always iterate over all elements.
– Frerich Raabe
Nov 9 '09 at 15:50
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