Function to handle joining multiple paths together (behaves like Python's `os.path.join` function). This handles resolving relative and absolute paths, e.g. `['foo/', '.', 'bar/baz/..', 'qux']` => `foo/bar/qux`

joinpath.coffee

joinPath = (paths...) ->
    finalPath = []

    for path in paths
        for tok, i in path.split('/')
            switch tok
                when '.' then continue
                when '..' then finalPath.pop()
                else finalPath.push tok

    finalPath.join('/')

joinpath.js

var joinPath,
  __slice = [].slice;

joinPath = function() {
  var finalPath, i, path, paths, tok, _i, _j, _len, _len1, _ref;
  paths = 1 <= arguments.length ? __slice.call(arguments, 0) : [];
  finalPath = [];
  for (_i = 0, _len = paths.length; _i < _len; _i++) {
    path = paths[_i];
    _ref = path.split('/');
    for (i = _j = 0, _len1 = _ref.length; _j < _len1; i = ++_j) {
      tok = _ref[i];
      switch (tok) {
        case '.':
          continue;
        case '..':
          finalPath.pop();
          break;
        default:
          finalPath.push(tok);
      }
    }
  }
  return finalPath.join('/');
};