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Swift: Testing optionals for nil
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In Xcode Beta 5, they no longer let you do:
var xyz : NSString?
if xyz {
// Do something using `xyz`.
}
This produces an error:
does not conform to protocol 'BooleanType.Protocol'
You have to use one of these forms:
if xyz != nil {
// Do something ...
How to iterate over arguments in a Bash script
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Use "$@" to represent all the arguments:
for var in "$@"
do
echo "$var"
done
This will iterate over each argument and print it out on a separate line. $@ behaves like $* except that when quoted the arguments are broken up properly if there are spaces in them:
sh test.sh 1 2...
How to do something to each file in a directory with a batch script
How do you iterate over each file in a directory with a .bat or .cmd file?
6 Answers
6...
Rails: fields_for with index?
Is there a method (or way to pull off similar functionality) to do a fields_for_with_index ?
9 Answers
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What kinds of patterns could I enforce on the code to make it easier to translate to another program
I am setting out to do a side project that has the goal of translating code from one programming language to another. The languages I am starting with are PHP and Python (Python to PHP should be easier to start with), but ideally I would be able to add other languages with (relative) ease. The plan ...
If list index exists, do X
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This doesn't account for negative indexes. The best way I know is try / except IndexError, but it'd be nice to have a concise way to get a bool
– Abram
Aug 6 '19 at 19:55
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Testing modules in rspec
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@lulalala No, it's a super class: ruby-doc.org/core-2.0.0/Class.html#method-c-new To test modules do something like this: let(:dummy_class) { Class.new { include ModuleToBeTested } }
– Timo
Oct 21 '13 at 7:24
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How to break out from a ruby block?
Here is Bar#do_things :
7 Answers
7
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How do you loop in a Windows batch file?
What is the syntax for a FOR loop in a Windows batch file?
8 Answers
8
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Just what is Java EE really? [closed]
...ed only once for all your classes instead of every library (EJB, JPA, etc) doing this scanning over and over itself. Also because of that, CDI annotations can be applied to EJB beans and JPA entity managers can be injected into them.
Why do I need something massive as JBoss just to compile simple c...