JSON strings can contain braces

balanced2.rb

JSON strings can contain {}.

test_data = ["{dsfgsdf}", "{asdf}, {sdfsdf}", "{{dfgd}, {sadf}}", "sdfd}{", "{asdfsad}, {sdfs}}", "{{asdf},{sdfsdf}", '{"test{{{"}, {"{{{fest"}']

test_data.each { |s|
  instring = false;
  res = s.split(//).reduce(0) { |sum, c|
    break sum if sum < 0
    instring = !instring if c == '"'
    if !instring
      sum +=1 if c == "{"
      sum -=1 if c == "}"
    end
    sum
  }
  puts s + " is #{res != 0 ? "no ":""}good!"
}

Output:

{dsfgsdf} is good!
{asdf}, {sdfsdf} is good!
{{dfgd}, {sadf}} is good!
sdfd}{ is no good!
{asdfsad}, {sdfs}} is no good!
{{asdf},{sdfsdf} is no good!
{"test{{{"}, {"{{{fest"} is good!