code: function (binding, subpath, newValue) {
        var args = Util.resolveArgs(
          arguments,
          function (x) { return x instanceof Binding ? 'binding' : null; }, '?subpath', 'newValue'
        );
        return this.update(args.binding, args.subpath, Util.constantly(args.newValue));
      }
docs: Set binding value.
  @param {Binding} [binding] binding to apply update to
  @param {String|Array} [subpath] subpath as a dot-separated string or an array of strings and numbers
  @param {*} newValue new value
  @return {TransactionContext} updated transaction context