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How do I check for null values in JavaScript?
... !user){
Which will check for empty strings (""), null, undefined, false and the numbers 0 and NaN
Please note that if you are specifically checking for numbers it is a common mistake to miss 0 with this method, and num !== 0 is preferred (or num !== -1 or ~num (hacky code that also checks agains...
Difference between objectForKey and valueForKey?
What is the difference between objectForKey and valueForKey ?
I looked both up in the documentation and they seemed the same to me.
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Convert a Map to a POJO
... looking at Jackson, but is seems I would have to convert the Map to JSON, and then the resulting JSON to the POJO.
8 Answ...
Best practice? - Array/Dictionary as a Core Data Entity Attribute [closed]
... I have noticed that collection types are not available as attribute types and would like to know what the most efficient way is of storing array/dictionary type data as an attribute (e.g. the elements that make up an address like street, city, etc. does not require a separate entity and is more con...
Can a class extend both a class and implement an Interface
Can a class extend both an interface and another class in PHP?
Basically I want to do this:
3 Answers
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How do you get centered content using Twitter Bootstrap?
I'm trying to follow a very basic example. Using the starter page and the grid system , I was hoping the following:
23 An...
How do I fetch lines before/after the grep result in bash?
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You can use the -B and -A to print lines before and after the match.
grep -i -B 10 'error' data
Will print the 10 lines before the match, including the matching line itself.
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Why did Rails4 drop support for “assets” group in the Gemfile
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Previously the assets group existed to avoid unintended compilation-on-demand in production. As Rails 4 doesn't behave like that anymore, it made sense to remove the asset group.
This is explained in more detail in the commit that changed that. I extracted some quotes with the actual answer.
Some ...
Converting ISO 8601-compliant String to java.util.Date
...Unfortunately, the time zone formats available to SimpleDateFormat (Java 6 and earlier) are not ISO 8601 compliant. SimpleDateFormat understands time zone strings like "GMT+01:00" or "+0100", the latter according to RFC # 822.
Even if Java 7 added support for time zone descriptors according to ISO ...
git discard all changes and pull from upstream
How do I fetch upstream repo and make it replace master? I only have one branch on my repo, which is master, and I completely messed it up, so I basically need to start over from the upstream. I think init will do the job, but is there an easier way?
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