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How to define a function in ghci across multiple lines?
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For guards (like your example), you can just put them all on one line and it works (guards do not care about spacing)
let abs n | n >= 0 = n | otherwise = -n
If you wanted to write your function with multiple definitions that pattern match on the arguments, like this:
fact 0 = 1
fact n =...
Converting bytes to megabytes
... it is not correct actually because mega means 1 000 000. There is a new standard name for 220 bytes, it is mebibyte (http://en.wikipedia.org/wiki/Mebibyte) and it gathers popularity.
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improv...
Insert into a MySQL table or update if exists
...m what I've found, this method is less problematic for auto-increment keys and other unique key collisions than REPLACE INTO, and it is more efficient.
– Andrew Ensley
May 11 '12 at 21:27
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Keep file in a Git repo, but don't track changes
...t solution to do this. First change the file you do not want to be tracked and use the following command:
git update-index --assume-unchanged FILE_NAME
and if you want to track the changes again use this command:
git update-index --no-assume-unchanged FILE_NAME
git-update-index documentation...
Elegant ways to support equivalence (“equality”) in Python classes
...om classes it is often important to allow equivalence by means of the == and != operators. In Python, this is made possible by implementing the __eq__ and __ne__ special methods, respectively. The easiest way I've found to do this is the following method:
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Understanding Python's “is” operator
...e value.
From the documentation for the is operator:
The operators is and is not test for object identity: x is y is true if and only if x and y are the same object.
Use the == operator instead:
print(x == y)
This prints True. x and y are two separate lists:
x[0] = 4
print(y) # prints [1...
How do you select a particular option in a SELECT element in jQuery?
...have been after changing the selected item of the dropdown. In version 1.6 and higher the prop() method is recommended:
$('.selDiv option:eq(1)').prop('selected', true)
In older versions:
$('.selDiv option:eq(1)').attr('selected', 'selected')
EDIT2: after Ryan's comment. A match on "Selection ...
Converting a list to a set changes element order
...at when I am converting a list to set the order of elements is changed and is sorted by character.
11 Answers
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Breadth First Vs Depth First
When Traversing a Tree/Graph what is the difference between Breadth First and Depth first? Any coding or pseudocode examples would be great.
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Simplest way to read json from a URL in java
This might be a dumb question but what is the simplest way to read and parse JSON from URL in Java ?
11 Answers
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