compressing object hierarchies in JavaScript

Question

Is there a generic approach to \"compressing\" nested objects to a single level:

var myObj = {
    a: \"hello\",
    b: {
        c: \"world\"
    }
}

compress(         


        

Answer 1

Here's a quick CoffeeScript version based off Matthew Crumley's answer (I didn't use includePrototype as I had no need for it):

flatten = (obj, into = {}, prefix = '', sep = '_') ->
  for own key, prop of obj
    if typeof prop is 'object' and prop not instanceof Date and prop not instanceof RegExp
      flatten prop, into, prefix + key + sep, sep
    else
      into[prefix + key] = prop
  into

And a basic unflatten version, which would undoubtedly fail with repeated separators and other such trickiness:

unflatten = (obj, into = {}, sep = '_') ->
  for own key, prop of obj
    subKeys = key.split sep
    sub = into
    sub = (sub[subKey] or= {}) for subKey in subKeys[...-1]
    sub[subKeys.pop()] = prop
  into

FWIW, I use these functions to push object graphs into Redis hashes, which only support a single depth of key/value pairs.