(function (tree) {
tree.Paren = function (node) {
this.value = node;
}; tree.Paren.prototype = {
toCSS: function (env) { return '(' + this.value.toCSS(env) + ')'; }, eval: function (env) { return new(tree.Paren)(this.value.eval(env)); }
};
})(require('../tree'));