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Why is “if not someobj:” better than “if someobj == None:” in Python?
...bject has a __len__ special method (as do container built-ins, list, dict, set, tuple, ...), it calls this method, considering a container False if it is empty (length is zero).
Otherwise, the object is considered True unless it is None in which case, it is considered False.
In the second test, th...
Is there a Java equivalent or methodology for the typedef keyword in C++?
...re readable for humans. Basically, it's like an enum but without a limited set of values.
– weberc2
Jan 2 '15 at 23:43
...
Xcode debugger doesn't print objects and shows nil, when they aren't
...top left corner near start/stop buttons, then "Edit scheme...", then "Run" settings, then "Info" tab, then "Build Configuration". Here set "Debug". If it was on "Release" that's the matter you saw all nils).
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warning about too many open figures
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What is pseudopolynomial time? How does it differ from polynomial time?
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Alternate FizzBuzz Questions [closed]
...5(2) 7(1)")
Given a string of expressions (only variables, +, and -) and a set of variable/value pairs (i.e. a=1, b=7, c=3, d=14) return the result of the expression ("a + b+c -d" would be -3).
These were for Java, and you could use the standard libraries so some of them can be extremely easy (lik...
How to run a makefile in Windows?
...les (x86)\Microsoft Visual Studio 9.0\Common7\Tools for VS2008). This will set up the environment to run nmake and find the compiler tools.
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Serving static files with Sinatra
...
Without any additional configuration, Sinatra will serve assets in public. For the empty route, you'll want to render the index document.
require 'rubygems'
require 'sinatra'
get '/' do
File.read(File.join('public', 'index.html'))
end
Routes should return a String which become ...
Why do you have to link the math library in C?
...ed libraries, and even when statically linking, the standard libraries are set up so that unused code can be discarded, so none of these are good reasons anymore.
– ephemient
Jun 23 '09 at 17:38
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List comprehension: Returning two (or more) items for each item
...='list(chain.from_iterable((f(x), g(x)) for x in range(3)))',
setup='gc.enable(); from itertools import chain; f = lambda x: x + 2; g = lambda x: x ** 2')
print timeit(stmt='list(chain.from_iterable(fg(x) for x in range(3)))',
setup='gc.enable(); from itertools import chai...