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Is there a difference between “throw” and “throw ex”?

... Yes, there is a difference; throw ex resets the stack trace (so your errors would appear to originate from HandleException) throw doesn't - the original offender would be preserved. static void Main(string[] args) { try { Method2(); } ...
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Should I use multiplication or division?

... Python: time python -c 'for i in xrange(int(1e8)): t=12341234234.234 / 2.0' real 0m26.676s user 0m25.154s sys 0m0.076s time python -c 'for i in xrange(int(1e8)): t=12341234234.234 * 0.5' real 0m17.932s user 0m16.481s sys 0m0.048s multi...
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Why does Stream not implement Iterable?

...hing that can only be used once — more like an Iterator. If Stream extended Iterable then existing code might be surprised when it receives an Iterable that throws an Exception the second time they do for (element : iterable). ...
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How to change the opacity (alpha, transparency) of an element in a canvas element after it has been

... seem to affect image drawing. //works with shapes but not with images ctx.fillStyle = "rgba(255, 255, 255, 0.5)"; I have concluded that setting the globalCompositeOperation works with images. //works with images ctx.globalCompositeOperation = "lighter"; I wonder if there is some kind third ...
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How to get all subsets of a set? (powerset)

... The Python itertools page has exactly a powerset recipe for this: from itertools import chain, combinations def powerset(iterable): "powerset([1,2,3]) --> () (1,) (2,) (3,) (1,2) (1,3) (2,3) (1,2,3)" s = list(iterable) return chain.from_it...
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Why is parenthesis in print voluntary in Python 2.7?

... In Python 2.x print is actually a special statement and not a function*. This is also why it can't be used like: lambda x: print x Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the co...
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How can I determine if a JavaScript variable is defined in a page? [duplicate]

...ariable is defined in a page? Suppose I want to check if a variable named "x" is defined in a page, if I do if(x != null) , it gives me an error. ...
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Why can't non-default arguments follow default arguments?

Why does this piece of code throw a SyntaxError? 4 Answers 4 ...
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Relationship between SciPy and NumPy

...'s almost certainly a scipy.foo . Most of the time, the two appear to be exactly the same, oftentimes even pointing to the same function object. ...
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What do you call the -> operator in Ruby?

...s"), a lambda defined using -> is called lambda literal. succ = ->(x){ x+1 } succ.call(2) The code is equivalent to the following one. succ = lambda { |x| x + 1 } succ.call(2) Informally, I have heard it being called stabby lambda or stabby literal. ...