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When should I use nil and NULL in Objective-C?
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This accepted answer fails to acknowledge that [NSNull null] is a very different beast. To quote from NSNull Class Reference, "The NSNull class defines a singleton object used to represent null values in collection objects (which don’t allow nil values)." ...
How to resolve symbolic links in a shell script
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realpath is now (Jan 2012) part of coreutils and backwards compatible with the debian and BSD variant
– pixelbeat
Apr 16 '12 at 7:43
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How to go back (ctrl+z) in vi/vim
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I know that most of my answer is duplicated with those already present, but the value added of my answer is redo as Ctrl + r (lower case r) based on the documentation. Nobody before put it here. In addition, I tried to make the ...
How to remove RVM (Ruby Version Manager) from my system
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Run:
rvm implode
Now you need to uninstall the RVM gem using:
gem uninstall rvm
Check if there are any remaining RVM files in your home directory, if yes remove them.
Go to the home directory and list all hidden files:
ls -a
rm .rvm
rm...
Easy way to see saved NSUserDefaults?
... I've found this has changed in later versions of XCode. You'll now find it in a directory under the current ios version number instead of User - eg /users/your user name/Library/Application Support/iPhone Simulator/4.3/Applications
– nevster
May 21 ...
setMaxResults for Spring-Data-JPA annotation?
... result = repository.findByUsername("Matthews", topTen);
If you need to know the context of the result (which page is it actually? is it the first one? how many are there in total?), use Page as return type:
public interface UserRepository extends Repository<User, Long> {
Page<User>...
Why would someone use WHERE 1=1 AND in a SQL clause?
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If the list of conditions is not known at compile time and is instead built at run time, you don't have to worry about whether you have one or more than one condition. You can generate them all like:
and <condition>
and concatenate them all together....
[ :Unexpected operator in shell programming [duplicate]
... This answer is partially wrong. The fully correct one is the now top-voted by Nietzche-jou. sh supports [. == works in Bash built-ins [[, test and [ while a single = is required by POSIX version of [ and test. (Bash manual says the same, BTW.) Requiring Bash because of this is needless...
How to delete multiple values from a vector?
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@BenBolker ah I didn't know that "duplicated" predicate :(( now what, shall I delete my answer or change it to show only yours instead?
– Özgür
Apr 3 '15 at 12:11
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How do I perform a Perl substitution on a string while keeping the original?
...tion is more useful as a shibboleth than good code; good Perl coders will know it and understand it, but it's much less transparent and readable than the two-line copy-and-modify couplet you're starting with.
In other words, a good way to do this is the way you're already doing it. Unnecessary con...