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What does the “map” method do in Ruby?
I'm new to programming. Can someone explain what .map would do in:
7 Answers
7
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Eclipse Kepler for OS X Mavericks request Java SE 6
I have just made a clean installation of OS X Mavericks , and I have downloaded Eclipse Kepler , but if I execute it, gives me this message:
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In Python, if I return inside a “with” block, will the file still close?
...
Yes, it acts like the finally block after a try block, i.e. it always executes (unless the python process terminates in an unusual way of course).
It is also mentioned in one of the examples of PEP-343 which is the specification for the with statement:
with locked(myLock):
# Code here exec...
How to filter a dictionary according to an arbitrary condition function?
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And here is a good explanation why the function call dict() is slower than the constructor/literal syntax {} doughellmann.com/2012/11/…
– dorvak
Jul 10 '13 at 9:37
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Difference between & and && in Java? [duplicate]
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& is bitwise AND operator comparing bits of each operand.
For example,
int a = 4;
int b = 7;
System.out.println(a & b); // prints 4
//meaning in an 32 bit system
// 00000000 00000000 00000000 00000100
// 00000000 00000000 00000000 00000111
// ===================================
// 0...
Why are Where and Select outperforming just Select?
...t of constructing the new state of the where iterator, which is more complex than the simple iterator that the Select version uses.
As you can see, for a given n, the Select version is a constant, whereas the Where+Select version is a linear equation with p(valid) as a variable. The actual values ...
application/x-www-form-urlencoded or multipart/form-data?
In HTTP there are two ways to POST data: application/x-www-form-urlencoded and multipart/form-data . I understand that most browsers are only able to upload files if multipart/form-data is used. Is there any additional guidance when to use one of the encoding types in an API context (no browser...
JavaScript: How to pass object by value?
...y may be to set o as the prototype of a new object.
var o = {};
(function(x){
var obj = Object.create( x );
obj.foo = 'foo';
obj.bar = 'bar';
})(o);
alert( o.foo ); // undefined
So any properties you add to obj will be not be added to o. Any properties added to obj with the same prop...
What is your favorite C programming trick? [closed]
For example, I recently came across this in the linux kernel:
37 Answers
37
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Reverse Range in Swift
...gh:1,by:-1) { print(i) } // 5 4 3 2 1
stide(from:to:by:) is similar but excludes the last value
for i in stride(from:5,to:0,by:-1) { print(i) } // 5 4 3 2 1
Update For latest Swift 2
First of all, protocol extensions change how reverse is used:
for i in (1...5).reverse() { print(i) } // 5 4 3...