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What is the difference between pluck and collect in Rails?
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When you do:
User.first.gifts.collect(&:id)
You have objects with all fields loaded and you simply get the id thanks to the method based on Enumerable.
So:
if you only need the id with Rails 4, use ids: User.first.gifts.ids
if you only need some fields with Rails 4, use pluck: User.first...
How to avoid having class data shared among instances?
...problem you face is that x.list and y.list are the same list, so when you call append on one, it affects the other.
– Matt Moriarity
Nov 5 '09 at 14:04
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Flexbox not giving equal width to elements
...t has up to 5 items and as little as 3, but it's not dividing the width equally between all the elements.
2 Answers
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Emacs mode for Stack Overflow's markdown
I am using Org-mode in Emacs to handle all my technical documentation. I would like to use Emacs to prepare questions that I have for Stack Overflow. Is there an Emacs mode for that, or even better, an extension for Org-mode to handle Stack Overflow formatting? Ideally it should include all formatti...
How to search for occurrences of more than one space between words in a line
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Why are you using anchors at all? He's looking for spaces embedded somewhere in the lines.
– Tim Pietzcker
Sep 21 '10 at 9:43
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What is the meaning of the term arena in relation to memory?
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An arena is just a large, contiguous piece of memory that you allocate once and then use to manage memory manually by handing out parts of that memory. For example:
char * arena = malloc(HUGE_NUMBER);
unsigned int current = 0;
void * my_malloc(size_t n) { current += n; return arena +...
Homebrew: List only installed top level formulas
I'm looking for a way to show only the formulas I installed without the installed dependencies.
I want to have a list of all the programs I actually installed, without all noise of the dependencies.
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How to import other Python files?
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importlib was added to Python 3 to programmatically import a module.
It is just a wrapper around __import__, see the docs.
import importlib
moduleName = input('Enter module name:')
importlib.import_module(moduleName)
Note: the .py extension should be removed from mod...
What is the difference between a .xib file and a .storyboard?
...ated .xib with it. Storyboard achieves two things:
.storyboard is essentially one single file for all your screens in the app and it shows the flow of the screens. You can add segues/transitions between screens, this way. So, this minimizes the boilerplate code required to manage multiple screens....
How to loop through all but the last item of a list?
... would indicate I answered the question he asked, if not the question he really wanted to ask. Asker is welcome to demote this answer.
– freespace
May 27 '09 at 11:35
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