instance method JSON::State#space_before

JSON 形式の文字列中で JavaScript のオブジェクトを表す部分にある ':' の前に挿入する文字列を返します。

require "json"

json_state = JSON::State.new(space_before: "")
json_state.space_before             # => ""
puts JSON.generate([1, 2, { name: "tanaka", age: 19 }], json_state)
# => [1,2,{"name":"tanaka","age":19}]

json_state = JSON::State.new(space_before: " ")
json_state.space_before             # => " "
puts JSON.generate([1, 2, { name: "tanaka", age: 19 }], json_state)
# => [1,2,{"name" :"tanaka","age" :19}]