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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:
fac...
Difference between break and continue statement
...necessary to exit a loop before the loop has finished fully iterating over all the step values. For example, looping over a list of numbers until you find a number that satisfies a certain condition. Or looping over a stream of characters from a file until a certain character is read.
In the follow...
Can scripts be inserted with innerHTML?
... that you've inserted as DOM text.
MooTools will do this for you automatically, and I'm sure jQuery would as well (depending on the version. jQuery version 1.6+ uses eval). This saves a lot of hassle of parsing out <script> tags and escaping your content, as well as a bunch of other "gotchas...
compareTo() vs. equals()
...ls() because to me this seems to be the most natural method for it. After all, its name already says what it is intended to do. However, a colleague of mine recently told me had been taught to use compareTo() == 0 instead of equals() . This feels unnatural (as compareTo() is meant to provide a...
Bootstrap modal appearing under background
...tive position this behavior will occur.
Make sure the modal container and all of its parent elements are positioned the default way to fix the problem.
Here are a couple ways to do this:
Easiest way is to just move the modal div so it is outside any elements with special positioning. One good p...
Python to print out status bar and percentage
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There's a Python module that you can get from PyPI called progressbar that implements such functionality. If you don't mind adding a dependency, it's a good solution. Otherwise, go with one of the other answers.
A simple example of how to use it:
import progressbar
from time...
How are zlib, gzip and zip related? What do they have in common and how are they different?
The compression algorithm used in zlib is essentially the same as that in gzip and zip . What are gzip and zip ? How are they different and how are they same?
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“No X11 DISPLAY variable” - what does it mean?
I am trying to install a Java application on my Linux machine (Slackware).
10 Answers
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MySQL SELECT only not null values
...hough...
SELECT val1 AS val
FROM your_table
WHERE val1 IS NOT NULL
UNION ALL
SELECT val2
FROM your_table
WHERE val2 IS NOT NULL
/*And so on for all your columns*/
The disadvantage of the above is that it scans the table multiple times once for each column. That may possibly be avoided by the b...
How do you rotate a two dimensional array?
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One of my favorite SO answers of all time. Very instructive!
– g33kz0r
Apr 4 '13 at 2:49
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