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Git submodule inside of a submodule (nested submodules)
Is it possible for a git submodule to be made of several other git submodules, and the super git repo to fetch the contents for each submodule?
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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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How to get a index value from foreach loop in jstl
I have a value set in the request object like the following,
5 Answers
5
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Favorite way to create an new IEnumerable sequence from a single value?
I usually create a sequence from a single value using array syntax, like this:
4 Answers
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C# - Multiple generic types in one list
This is probably not possible, but I have this class:
3 Answers
3
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C++ const map element access
I tried to use the operator[] access the element in a const C++ map, but this method failed. I also tried to use "at()" to do the same thing. It worked this time. However, I could not find any reference about using "at()" to access element in a const C++ map. Is "at()" a newly added function in C++ ...
Unsigned keyword in C++
Does the unsigned keyword default to a specific data type in C++? I am trying to write a function for a class for the prototype:
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How do I install imagemagick with homebrew?
I'm trying to install Imagemagick on OSX Lion but something is not working as expected.
5 Answers
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Autocomplete applying value not label to textbox
Im having troubles trying to get the autocomplete to work properly.
3 Answers
3
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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
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Update
data.table v1.9.6+ now supports OP's original attempt and the following answer is no longer necessary.
You can use DT[order(-rank(x), y)].
x y v
1: c 1 7
2: c 3 8
3: c 6 9
4: b 1 1
5: b 3 2
6: b 6 3
7: a 1 4
8: a 3...