I'm parsing JSON from an API. I have a foo element that's a hash sometimes, and an array of hashes, other times.
foo: { ... }
foo: [
{ ... },
{ ... }
]
I'd like to just use Array(foo) to always get the an array with at least the one element, but it converts the hash to [[..., ...], [..., ...]]. Is there an elegant way to handle this, besides using foo.is_a?(Hash/Array)?
Adding to @yez answer, if you are not using activesupport, you can extend Array to have a wrap function:
def Array.wrap(object)
if object.nil?
[]
elsif object.respond_to?(:to_ary)
object.to_ary || [object]
else
[object]
end
end
Copied from http://apidock.com/rails/Array/wrap/class
Another crude way to implement it is:
def Array.wrap(object)
return [] if object.nil?
[object].flatten(1)
end
flatten(1) to avoid flattening nested arrays.
In a Rails environment, with access to activesupport:
You could use Array.wrap
foo = { a: :b }
=> {:a=>:b}
Array.wrap(foo)
=> [{:a=>:b}]
Array.wrap([1,2,3])
=> [1, 2, 3]
Without Rails, you could do gem install activesupport and then in your code: require 'activesupport'
If you want to solve it using plain Ruby then you can push the item(s) (either Array of Hashes or Hash) to an empty array and then flatten the array like following:
2.0.0-p247 :001 > [{a:1}].flatten(1)
=> [{:a=>1}]
2.0.0-p247 :002 > [[{a:1},{b:2}]].flatten(1)
=> [{:a=>1}, {:b=>2}]
i.e. [foo].flatten(1) should work.
push, just: [{a:1}].flatten / [[{a:1},{b:2}]].flatten
[].push(obj) is equivalent to [obj][*[obj]]; e.g., [*[{a:1}]] #=> [{:a=>1}], [*[{a:1, b:2}]] #=> [{:a=>1, :b=>2}].
ActiveSupportto perform a simple calculation? There's nothing simpler than the way @Veet does it. Even if the lack of a Rails tag was an oversight, you cannot very well add it now.