scala - Scala中的Seq和Set有什么区别

Question

var seq = Seq[String]()
seq = seq :+ "hello"

var set = Set[String]()
set += "hello"

Seq和Set有什么区别？

Answer 1

序号

http://www.scala-lang.org/api/current/scala/collection/Seq.html

Sequences always have a defined order of elements. Sequences provide a method apply for indexing.

Seq与 java.util.List相似。

放

http://www.scala-lang.org/api/current/scala/collection/Set.html

A set is a collection that contains no duplicate elements.

这在数学意义上非常类似于“集合”: http://en.wikipedia.org/wiki/Set_(mathematics)
Set与 java.util.Set相似。