code: function abs(input) {
      if (!input) { return process.cwd(); }
      if (input.charAt(0) === "/") { return input; }
      if (input.charAt(0) === "~" && input.charAt(1) === "/") {
          input = ul.HOME_DIR + input.substr(1);
      }
      return path.resolve(input);
  }
docs: abs
  Computes the absolute path of an input.
  
  @name abs
  @function
  @param {String} input The input path (if not provided, the current
  working directory will be returned).
  @return {String} The absolute path.