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Determine if a function exists in bash
..., built-in function, external command, or just not defined. Example:
$ LC_ALL=C type foo
bash: type: foo: not found
$ LC_ALL=C type ls
ls is aliased to `ls --color=auto'
$ which type
$ LC_ALL=C type type
type is a shell builtin
$ LC_ALL=C type -t rvm
function
$ if [ -n "$(LC_ALL=C type -t rvm)...
C# switch statement limitations - why?
...a big if-else statement.
Each case must be unique and evaluated
statically. The switch statement does
a constant time branch regardless of
how many cases you have. The if-else
statement evaluates each condition
until it finds one that is true.
In fact, the C# switch statement is n...
Python syntax for “if a or b or c but not all of them”
...three command line arguments. (Either it runs on default behavior or needs all three values specified.)
15 Answers
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Benefits of using the conditional ?: (ternary) operator
...
I would basically recommend using it only when the resulting statement is extremely short and represents a significant increase in conciseness over the if/else equivalent without sacrificing readability.
Good example:
int result = Check...
For files in directory, only echo filename (no path)
...s Parameter Expansion which is native to the shell and does not require a call to an external binary such as basename
However, might I suggest just using find
find /home/user -type f -printf "%f\n"
share
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GIT commit as different user without email / or only email
...name
The separation of the characters probably indicates that spaces are allowed, it could also be resembling initials.
The username has to be followed by 1 space, extra spaces will be truncated
<author@example.com> = optional email address
Must always be between < > signs.
The ema...
Proper MIME media type for PDF files
...lication/pdf type should be used - unless you need to be compatible with really old software don't use x-pdf ...
– janniks
Feb 3 at 10:39
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Can you use if/else conditions in CSS?
...ks something like this:
p {
background-position: <?php echo (@$_GET['foo'] == 'bar')? "150" : "4"; ?>px 8px;
}
In this case, you will however have a performance impact, since caching such a stylesheet will be difficult.
...
linq query to return distinct field values from a list of objects
... it's easy - project to that with Select and then use the normal Distinct call.)
In MoreLINQ we have the DistinctBy operator which you could use:
var distinct = list.DistinctBy(x => x.typeID);
This only works for LINQ to Objects though.
You can use a grouping or a lookup, it's just somewhat ...
How to return dictionary keys as a list in Python?
...]
New unpacking generalizations (PEP 448) were introduced with Python 3.5 allowing you to now easily do:
>>> newdict = {1:0, 2:0, 3:0}
>>> [*newdict]
[1, 2, 3]
Unpacking with * works with any object that is iterable and, since dictionaries return their keys when iterated throug...