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What's an elegant way to conditionally add a class to an HTML element in a view?

...lly you should represent success with boolean true or a numeric record ID, and failure with boolean false or nil. This way you can just test your variable: <div class="<%= 'ok' if @success %>"> A second form using the ternary ?: operator is useful if you want to choose between two cl...
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Java concurrency: Countdown latch vs Cyclic barrier

I was reading through the java.util.concurrent API , and found that 14 Answers 14 ...
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Ruby on Rails Callback, what is difference between :before_save and :before_create?

Could you explain in detail what the :before_save and :before_create Ruby on Rails callbacks are, and what they have to do with Rails validations? Does validation occur after :before_save or :before_create ? ...
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What is the difference between Raising Exceptions vs Throwing Exceptions in Ruby?

Ruby has two different exceptions mechanisms: Throw/Catch and Raise/Rescue. 3 Answers ...
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Postgres: clear entire database before re-creating / re-populating from bash script

... I'd just drop the database and then re-create it. On a UNIX or Linux system, that should do it: $ dropdb development_db_name $ createdb developmnent_db_name That's how I do it, actually. ...
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“aapt” IOException error=2, No such file or directory" why can't I build my gradle on jenkins?

...e following similar error on Ubuntu 13.10: Cannot run program "/usr/local/android-sdk-linux/build-tools/19.0.3/aapt": error=2, No such file or directory And this answer fixed it for me: To get aapt working (this fixed my issues with the avd as well) just install these two packages: sudo apt-g...
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Git resolve conflict using --ours/--theirs for all files

Is there a way to resolve conflict for all files using checkout --ours and --theirs ? I know that you can do it for individual files but couldn't find a way to do it for all. ...
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How do I measure time elapsed in Java? [duplicate]

...answers posted so far are quite right. If you are measuring elapsed time, and you want it to be correct, you must use System.nanoTime(). You cannot use System.currentTimeMillis(), unless you don't mind your result being wrong. The purpose of nanoTime is to measure elapsed time, and the purpose of...
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Git: Recover deleted (remote) branch

...ull --no-reflogs | grep commit to find the HEAD commit of deleted branch and get them back. share | improve this answer | follow | ...
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How do you do relative time in Rails?

... edited Jun 20 '12 at 15:43 Andrew Marshall 87.3k1818 gold badges202202 silver badges204204 bronze badges answered Oct 12 '08 at 19:18 ...