After calling `search` function of String object, the property of global object RegExp does not effect.

var str = "X98Y87Z65";
var reg = /^X(\d+)Y(\d+)Z(\d+)$/;
str.search(reg);
print(RegExp.$1); // must be 98, but empty string
print(RegExp.$2); // must be 87, but empty string
print(RegExp.$3); // must be 65, but empty string

After calling `search` function of String object, the property of global object RegExp does not effect.