jbuilder

Jbuilder#array!

Turns the current element into an array and iterates over the passed collection, adding each iteration as
an element of the resulting array.

Example:

  json.array!(@people) do |person|
    json.name person.name
    json.age calculate_age(person.birthday)
  end

  [ { "name": David", "age": 32 }, { "name": Jamie", "age": 31 } ]

If you are using Ruby 1.9+, you can use the call syntax instead of an explicit extract! call:

  json.(@people) { |person| ... }

It's generally only needed to use this method for top-level arrays. If you have named arrays, you can do:

  json.people(@people) do |person|
    json.name person.name
    json.age calculate_age(person.birthday)
  end

  { "people": [ { "name": David", "age": 32 }, { "name": Jamie", "age": 31 } ] }

If you omit the block then you can set the top level array directly:

  json.array! [1, 2, 3]

  [1,2,3]

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