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Iterating over each line of ls -l output
...
Set IFS to newline, like this:
IFS='
'
for x in `ls -l $1`; do echo $x; done
Put a sub-shell around it if you don't want to set IFS permanently:
(IFS='
'
for x in `ls -l $1`; do echo $x; done)
Or use while | read instead:
...
How to play with Control.Monad.Writer in haskell?
...Writer
ghci> let logNumber x = writer (x, ["Got number: " ++ show x])
Now logNumber is a function that creates writers. I can ask for its type:
ghci> :t logNumber
logNumber :: (Show a, MonadWriter [String] m) => a -> m a
Which tells me that the inferred type is not a function that r...
How can I have linebreaks in my long LaTeX equations?
...
If your equation does not fit on a single line, then the multline environment probably is what you need:
\begin{multline}
first part of the equation \\
= second part of the equation
\end{multline}
If you also need ...
ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.al
...understood way to evaluate
an array in boolean context: it could mean True if any element is
True, or it could mean True if all elements are True, or True if the array has non-zero length, just to name three possibilities.
Since different users might have different needs and different assumptions, ...
How do I set a conditional breakpoint in gdb, when char* x points to a string whose value equals “he
Can I specify that I want gdb to break at line x when char* x points to a string whose value equals "hello" ? If yes, how?
...
Ruby: How to turn a hash into HTTP parameters?
...re, considering all the major Ruby web frameworks are built on top of Rack now.
– iain
May 16 '13 at 13:10
@EdRuder Ac...
How to detect orientation change?
...on while using the camera with AVFoundation, and found that the didRotate (now deprecated) & willTransition methods were unreliable for my needs. Using the notification posted by David did work, but is not current for Swift 3.x/4.x.
Swift 4.2
The notification name has been changed.
The closure...
How to delete a file or folder?
..._path.mkdir()
file_path = directory_path / 'file'
file_path.touch()
and now:
>>> file_path.is_file()
True
Now let's delete them. First the file:
>>> file_path.unlink() # remove file
>>> file_path.is_file()
False
>>> file_path.exists()
False
We can use...
How do I run a single test with Nose in Pylons
...ler should work, where the file is named test_controller.py.
To run a specific test class and method use a path of the form module.path:ClassNameInFile.method_name, that is, with a colon separating the module/file path and the objects within the file. module.path is the relative path to the file (e...
How can I visualize per-character differences in a unified diff file?
...y I get a patch created with git format-patch . The file is basically a unified diff with some metadata. If I open the file in Vim, I can see which lines have been modified, but I cannot see which characters in the changed lines differ. Does anyone know a way (in Vim, or some other free software ...