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Why is there no xrange function in Python3?
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Some performance measurements, using timeit instead of trying to do it manually with time.
First, Apple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s...
How can I produce an effect similar to the iOS 7 blur view?
...g the effect? Just draw a UIToolbar behind your view.
myView.backgroundColor = [UIColor clearColor];
UIToolbar* bgToolbar = [[UIToolbar alloc] initWithFrame:myView.frame];
bgToolbar.barStyle = UIBarStyleDefault;
[myView.superview insertSubview:bgToolbar belowSubview:myView];
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PHP - concatenate or directly insert variables in string
I am wondering, What is the proper way for inserting PHP variables into a string?
This way:
14 Answers
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How to test valid UUID/GUID?
...here. The following regex takes this into account and will return a match for a NIL UUID. See below for a UUID which only accepts non-NIL UUIDs. Both of these solutions are for versions 1 to 5 (see the first character of the third block).
Therefore to validate a UUID...
/^[0-9a-f]{8}-[0-9a-f]{4}-[...
Avoiding instanceof in Java
...operations is considered a "code smell". The standard answer is "use polymorphism". How would I do it in this case?
9 Ans...
Overriding fields or properties in subclasses
I have an abstract base class and I want to declare a field or a property that will have a different value in each class that inherits from this parent class.
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JS: iterating over result of getElementsByClassName using Array.forEach
...rn browsers (pretty much anything other IE <= 8), you can call Array's forEach method, passing it the list of elements (be it HTMLCollection or NodeList) as the this value:
var els = document.getElementsByClassName("myclass");
Array.prototype.forEach.call(els, function(el) {
// Do stuff her...
When is memoization automatic in GHC Haskell?
...e at most once per time that its surrounding lambda-expression is entered, or at most once ever if it is at top level. Determining where the lambda-expressions are can be a little tricky when you use syntactic sugar like in your example, so let's convert these to equivalent desugared syntax:
m1' =...
What is a monad?
... mathematician. An alternative term is computation builder which is a bit more descriptive of what they are actually useful for.
They are a pattern for chaining operations. It looks a bit like method chaining in object-oriented languages, but the mechanism is slightly different.
The pattern is mostl...
财务计算器拓展：复利计算、平均值、中位数、众数、方差计算 - App Invento...
Financial Calculator Extension
精心打造的“财务计算器”扩展，为您的Android应用程序增添先进的财务和统计功能。此扩展让您能够执行广泛的财务计算，从简单利息和复利到净现值和投资回报率。它还使您能够进行基本的统计计算...