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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 do I access properties of a javascript object if I don't know the names?
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Did you just make that last one up and actually got away with it? Well done... =)
– nickl-
Sep 25 '12 at 15:03
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Could not load file or assembly 'System.Web.Http 4.0.0 after update from 2012 to 2013
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I fixed this by reinstalling the NuGet package, which corrects broken dependencies. From the package manager, run:
Update-Package Microsoft.AspNet.WebApi -reinstall
shar...
Why is the default value of the string type null instead of an empty string?
It's quite annoying to test all my strings for null before I can safely apply methods like ToUpper() , StartWith() etc...
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Running multiple async tasks and waiting for them all to complete
...ed to run multiple async tasks in a console application, and wait for them all to complete before further processing.
9 Ans...
Cannot generate iOS App archive in xcode
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Check Build Settings:
Skip install is NO for the main project target
Skip install is YES for framework (sub-projects) targets
In Build Phases for sub-projects, Copy Headers needs to be in Project, not Public (does not apply if building static library)
Inst...
How to remove RVM (Ruby Version Manager) from my system
... that will pull it:
rvm implode
This will remove the rvm/ directory and all the rubies built within it. In order to remove the final trace of rvm, you need to remove the rvm gem, too:
gem uninstall rvm
If you've made modifications to your PATH you might want to pull those, too. Check your .bas...
Postgres DB Size Command
What is the command to find the size of all the databases?
10 Answers
10
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What's the best CRLF (carriage return, line feed) handling strategy with Git?
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Almost four years after asking this question, I have finally
found an answer that completely satisfies me!
See the details in github:help's guide to
Dealing with line endings.
Git allows you to set the line ending properties for a
repo directly using the text attribute in t...
Regex expressions in Java, \\s vs. \\s+
...e, whereas the second one matches one or many whitespaces. They're the so-called regular expression quantifiers, and they perform matches like this (taken from the documentation):
Greedy quantifiers
X? X, once or not at all
X* X, zero or more times
X+ X, one or more times
X{n} X, exactly n ti...