docs: function (binding, subpath, f) {
      var args = Util.resolveArgs(
        arguments,
        'binding', function (x) { return Util.canRepresentSubpath(x) ? 'subpath' : null; }, '?f'
      );
  
      return function (event) {
        var value = event.target.value;
        binding.set(args.subpath, args.f ? args.f(value) : value);
      };
    }