# File lib/execjs/external_runtime.rb, line 45
        def compile(source)
          @runtime.send(:runner_source).dup.tap do |output|
            output.sub!('#{source}') do
              source
            end
            output.sub!('#{encoded_source}') do
              encoded_source = encode_unicode_codepoints(source)
              MultiJson.encode("(function(){ #{encoded_source} })()")
            end
            output.sub!('#{json2_source}') do
              IO.read(ExecJS.root + "/support/json2.js")
            end
          end
        end