红宝石串?

N

A String object holds and manipulates an arbitrary sequence of bytes, typically representing characters. String objects may be created using ::new or as literals.

Because of aliasing issues, users of strings should be aware of the methods that modify the contents of a String object. Typically, methods with names ending in “!'' modify their receiver, while those without a “!'' return a new String. However, there are exceptions, such as #[]=.