When using Objects returned by the ActiveRecord collection proxy, using a loop if fine in a view, but sometimes I want to turn just one of the hash' common attributes into an array. I find I'm doing it a lot, which results in what appears to be somewhat verbose:
forum_roles = []
@forum #=> [{id: 0, name: 'a'},{id: 1, name: 'b'}]
@forum.each do |role|
forum_roles << role.name
end
forum_roles #=> ['a','b']
Just wondering if there's an easier way to arriving at ['a','b']
Use Array#map when you have an array of hashes
forum_roles = @forum.map { |role| role[:name] }
forum_roles # ['a','b']
UPDATE:
With ActiveRecord Objects, there's a shorcut as @vee commented
@forum.map(&:name)
If you have an ActiveRecord Relation and you only want an array of a column, use pluck
@forum.pluck(:name)
&:name isn't correct. That invokes role.name() on each hash, not role[:name]. That would work for an array of objects, but not an array of hashes.
@forum is an AR Relation, so isn't it safe to assume name is an attribute of presumably Role object?
@forum is indeed an AR relation which is why the OP can do forum_roles << role.name
pluck is plucking amazing.