flatten.js

function flatten(obj) {
   var result = {};

   if(obj === null || typeof obj !== 'object') {
      // error
   }

   for(k in obj) {
      value = obj[k];

      if(value === null) {
         // error.  have to put this here because null is an object
      } else if(typeof value === 'object') {
         nvalue = flatten(value);
         for(nk in nvalue)
            result[k + '.' + nk] = nvalue[nk];
      } else if(typeof value === 'string') {
         result[k] = value;
      } else if(typeof value === 'number') {
         result[k] = value.toString();
      } else {
         // error
      }
   }

   return result;
}