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(How) can I count the items in an enum?
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There's not really a good way to do this, usually you see an extra item in the enum, i.e.
enum foobar {foo, bar, baz, quz, FOOBAR_NR_ITEMS};
So then you can do:
int fuz[FOOBAR_NR_ITEMS];
Still not very nice though.
But of course you...
Changes in import statement python3
...a single function. In Python 2 you were permitted to be semi-lazy:
def sin_degrees(x):
from math import *
return sin(degrees(x))
Note that it already triggers a warning in Python 2:
a.py:1: SyntaxWarning: import * only allowed at module level
def sin_degrees(x):
In modern Python 2 co...
Find nearest latitude/longitude with an SQL query
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Additionally, it does not take into account the curvature of the earth. This would not be an issue for short search radii. Otherwise Evan's and Igor's answers are more complete.
– John Vance
N...
Sorting list based on values from another list?
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Shortest Code
[x for _,x in sorted(zip(Y,X))]
Example:
X = ["a", "b", "c", "d", "e", "f", "g", "h", "i"]
Y = [ 0, 1, 1, 0, 1, 2, 2, 0, 1]
Z = [x for _,x in sorted(zip(Y,X))]
print(Z) # ["a", "d", "h", "b", "c", "e", "i", "f"...
Can I list-initialize a vector of move-only type?
...nitializer list elements in the current revision of the language.
Specifically, we have:
typedef const E& reference;
typedef const E& const_reference;
typedef const E* iterator;
typedef const E* const_iterator;
const E* begin() const noexcept; // first element
const E* end() const noexce...
What does the “@” symbol mean in reference to lists in Haskell?
...hout the @, you'd have to choose between (1) or (2):(3).
This syntax actually works for any constructor; if you have data Tree a = Tree a [Tree a], then t@(Tree _ kids) gives you access to both the tree and its children.
s...
Where do I find the current C or C++ standard documents?
...9:1990 Hardcopy available from SAI Global ($88 + shipping)
You cannot usually get old revisions of a standard (any standard) directly from the standards bodies shortly after a new edition of the standard is released. Thus, standards for C89, C90, C99, C++98, C++03 will be hard to find for purchas...
Microsoft CDN for jQuery or Google CDN? [closed]
Does it actually matter which CDN you use to link to your jquery file or any javascript file for that matter. Is one potentially faster than the other? What other factors could play a role in which cdn you decide to use? I know that Microsoft, Yahoo, and Google all have CDN's now.
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How do I shuffle an array in Swift?
...Distance` in < Swift 4.1
let d: Int = numericCast(arc4random_uniform(numericCast(unshuffledCount)))
let i = index(firstUnshuffled, offsetBy: d)
swapAt(firstUnshuffled, i)
}
}
}
extension Sequence {
/// Returns an array with the contents of this...
Can not connect to local PostgreSQL
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This really looks like a file permissions error. Unix domain sockets are files and have user permissions just like any other. It looks as though the OSX user attempting to access the database does not have file permissions to acce...