code: function formatMoment(m, format) {
          var i = 5;
  
          function replaceLongDateFormatTokens(input) {
              return m.lang().longDateFormat(input) || input;
          }
  
          while (i-- && localFormattingTokens.test(format)) {
              format = format.replace(localFormattingTokens, replaceLongDateFormatTokens);
          }
  
          if (!formatFunctions[format]) {
              formatFunctions[format] = makeFormatFunction(format);
          }
  
          return formatFunctions[format](m);
      }
docs: format date using native date object