scala 元组

创建元组
val t1 = (1,2,3,4)
val t2 = ("java","scala",33)
查看值：
t2._1
res48: String = java

另一个方式创建元组

 val t4,(a,b,c) = ("hello","world","nihao")
t4: (String, String, String) = (hello,world,nihao)
a: String = hello
b: String = world
c: String = nihao

scala> a
res49: String = hello

scala> b
res50: String = world

scala> c
res51: String = nihao
 val t4,(a,b,c) = ("hello","world","nihao")
t4: (String, String, String) = (hello,world,nihao)
a: String = hello
b: String = world
c: String = nihao

scala> a
res49: String = hello

scala> b
res50: String = world

scala> c
res51: String = nihao val t4,(a,b,c) = ("hello","world","nihao")
t4: (String, String, String) = (hello,world,nihao)
a: String = hello
b: String = world
c: String = nihao

scala> a
res49: String = hello

scala> b
res50: String = world

scala> c
res51: String = nihao
t4._1
res53: String = hello

元组的遍历

t6.productIterator.foreach(i=>println(i))
1
2
3
4
test

拉链操作

val a1 = Array("java","scala","python")
a1: Array[String] = Array(java, scala, python)

scala> val a2 = Array(1,2,3)
a2: Array[Int] = Array(1, 2, 3)

scala> a1.zip(a2)
res55: Array[(String, Int)] = Array((java,1), (scala,2), (python,3))


val a3 = Array(1,2,3,4)
a3: Array[Int] = Array(1, 2, 3, 4)

scala> a1.zip(a3)
res56: Array[(String, Int)] = Array((java,1), (scala,2), (python,3))//多余的被舍弃

设置一个默认值，不会舍弃多余的值

 val x = "a"
x: String = a

scala> val y = 4
y: Int = 4

scala> a1.zipAll(a3,x,y)
res57: Array[(String, Int)] = Array((java,1), (scala,2), (python,3), (a,4))

scala> val a5 = a1.zipAll(a3,x,y)
a5: Array[(String, Int)] = Array((java,1), (scala,2), (python,3), (a,4))

scala> a5.unzip
重新返回原来的样子