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How to see if an object is an array without using reflection?
How can I see in Java if an Object is an array without using reflection?
And how can I iterate through all items without using reflection?
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How do RVM and rbenv actually work?
I am interested in how RVM and rbenv actually work.
5 Answers
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Can I make a function available in every controller in angular?
... a utility function foo that I want to be able to call from anywhere inside of my ng-app declaration. Is there someway I can make it globally accessible in my module setup or do I need to add it to the scope in every controller?
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Is a statically-typed full Lisp variant possible?
Is a statically-typed full Lisp variant possible? Does it even make sense for something like this to exist? I believe one of a Lisp language's virtues is the simplicity of its definition. Would static typing compromise this core principle?
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Is there any way to see the file system on the iOS simulator?
...here any way to browse the file system of a currently running or just killed iOS simulator? I'd settle for being able to see a specific app's files if there's a way to do that.
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Delete multiple remote branches in git
I have a team member who inadvertently pushed over 150 of his local branches to our central repo. Thankfully, they all have the same prefix. Using that prefix, is there a git command or cool little shell script I can use that will delete all of those at once?
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What is the difference between and ?
What is the difference between <html lang="en"> and <html lang="en-US"> ? What other values can follow the dash?
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what is the difference between a portlet and a servlet?
I am asked to work on portlets and portals.
5 Answers
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dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
When using summarise with plyr 's ddply function, empty categories are dropped by default. You can change this behavior by adding .drop = FALSE . However, this doesn't work when using summarise with dplyr . Is there another way to keep empty categories in the result?
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Boolean operators && and ||
According to the R language definition , the difference between & and && (correspondingly | and || ) is that the former is vectorized while the latter is not.
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