運算符而不是函數
sizeof:對象大小 sizeof expr ;類型大小 ?sizeof(type);參數包大小 sizeof 。。(name)不太懂
new :創建對象 ?new type
new[] ?:創建數組 new type[size]
delete :釋放對象 delete expr
delete[] :釋放數組 delete[] expr
throw: 拋出異常 throw expr
typeid: ?類型ID typeid(type) ? ;運行時類型ID typeid(expr);
explicit cast ?:類型轉換 cast_name<type>(expr)
noexcept :能否拋出異常noexcept(expr)