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All falsey values in JavaScript
...t is truthy
[], [[]] and [0] (thanks cloudfeet for the JavaScript Equality Table link)
Some more truthy values
These are just a few values that some people might expect to be falsey, but are actually truthy.
-1 and all non-zero negative numbers
' ', " ", "false", 'null'... all non-empty strin...
Calculating frames per second in a game
... mean the value of time that you calculated for the last frame. This way, all previous frames will be included, with the most recent frames weighted the most heavily.
– j_random_hacker
May 23 '13 at 20:37
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What do (lambda) function closures capture?
...the name and scope of the variable, not the object it's pointing to. Since all the functions in your example are created in the same scope and use the same variable name, they always refer to the same variable.
EDIT: Regarding your other question of how to overcome this, there are two ways that com...
how to use javascript Object.defineProperty
...rs = new Product("Sneakers",20);
sneakers.discount = 50; // 50, setter is called
sneakers.discount+= 20; // 70, setter is called
sneakers.discount+= 20; // 80, not 90!
alert(sneakers.discount); // getter is called
Note the last but one line: the responsibility for correct discount value was moved ...
Printf width specifier to maintain precision of floating-point value
...ier which can be applied to a floating point specifier that would automatically format the output to the necessary number of significant digits such that when scanning the string back in, the original floating point value is acquired?
...
performSelector may cause a leak because its selector is unknown
...for the C function pointer for the method corresponding to the controller. All NSObjects respond to methodForSelector:, but you can also use class_getMethodImplementation in the Objective-C runtime (useful if you only have a protocol reference, like id<SomeProto>). These function pointers are ...
Define css class in django Forms
... The only sane solution, I must say. Thank you!. Python code, and especially in form's definition, is the last place to put stuff for styling - these definitely belong to the templates.
– Boris Chervenkov
Nov 12 '11 at 23:09
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Can I zip more than two lists together in Scala?
...
Scala treats all of its different tuple sizes as different classes (Tuple1, Tuple2, Tuple3, Tuple4,...,Tuple22) while they do all inherit from the Product trait, that trait doesn't carry enough information to actually use the data values ...
Getting SyntaxError for print with keyword argument end=' '
...print ("foo" % bar, end=" ")
or
print "foo" % bar, end=" "
i.e. as a call to print with a tuple as argument.
That's obviously bad syntax (literals don't take keyword arguments). In Python 3.x print is an actual function, so it takes keyword arguments, too.
The correct idiom in Python 2.x for ...
How can I find script's directory with Python? [duplicate]
...
You need to call os.path.realpath on __file__, so that when __file__ is a filename without the path you still get the dir path:
import os
print(os.path.dirname(os.path.realpath(__file__)))
...