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#pragma mark in Swift?
...ractice anyway. Since extensions can implement protocols, you can e.g. put all of your table view delegate methods in an extension and group your code at a more semantic level than #pragma mark is capable of.
share
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postgresql return 0 if returned value is null
...ns the first of its arguments that is not null.
Null is returned only if all arguments are null. It is often
used to substitute a default value for null values when data is
retrieved for display.
Edit
Here's an example of COALESCE with your query:
SELECT AVG( price )
FROM(
SELECT *, cum...
virtualenv --no-site-packages and pip still finding global packages?
... My hero! If you just want to check if that is your issue really quickly, you can run printenv to see if PYTHONPATH is there, and if it is, run unset PYTHONPATH. You'll still have to go track down the problem if you don't want the issue to pop up anymore, but that'll let you get a fr...
Extract file basename without path and extension in bash [duplicate]
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You don't have to call the external basename command. Instead, you could use the following commands:
$ s=/the/path/foo.txt
$ echo "${s##*/}"
foo.txt
$ s=${s##*/}
$ echo "${s%.txt}"
foo
$ echo "${s%.*}"
foo
Note that this solution should work...
Why does C# have break if it's not optional? [duplicate]
...om the horse's mouth (MSDN) Why is the C# switch statement designed to not allow fall-through, but still require a break?.
Quoting the salient bits, this is why they don't allow fall-through:
This implicit fall-through behavior is often used to reduce the amount of code needed and often isn't an is...
What's the difference between lapply and do.call?
I'm learning R recently and confused by two function: lapply and do.call . It seems that they're just similar to map function in Lisp. But why are there two functions with such a different name? Why doesn't R just use a function called map ?
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What is the equivalent of “none” in django templates?
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None, False and True all are available within template tags and filters. None, False, the empty string ('', "", """""") and empty lists/tuples all evaluate to False when evaluated by if, so you can easily do
{% if profile.user.first_name == None...
How do I find the most recent git commit that modified a file?
...ts looking at the history of specific files (and directories), so you can call it like this:
git log my/file.c
If you really only want to list the one most recent commit, for example to use it in a script, use the -n 1 option:
git log -n 1 --pretty=format:%H -- my/file.c
--pretty=format:%h tel...
Preventing Laravel adding multiple records to a pivot table
...ems()->where('foreign_key', $foreignKey)->count() Which, well, actually performs an additional query too '^^ But I don't need to fetch and hydrate the whole collection unless I really need it.
– Silence
May 24 '15 at 13:57
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How to align checkboxes and their labels consistently cross-browsers
...lems that plagues me constantly. How do folks around Stack Overflow vertically align checkboxes and their labels consistently cross-browser ? Whenever I align them correctly in Safari (usually using vertical-align: baseline on the input ), they're completely off in Firefox and IE. Fix it ...