Scala List forall() 方法与示例

forall()方法用于检查给定谓词是否满足列表的所有元素。

Method Definition: def forall (p: (a) => Boolean) : Boolean

Return Type: It returns true if the stated predicate holds true for all the elements of the list else it returns false.

示例 #1：

// Scala program of forall()
// method
  
// Creating object
object GfG
{ 
  
    // Main method
    def main(args:Array[String])
    {
        // Creating a list
        val m1 = List(3, 6, 12, 9, 21)
          
        // Applying forall method
        val result = m1.forall(y => {y % 3 == 0})
          
        // Displays output
        println(result)
      
    }
} 

输出：

true

示例 #2：

// Scala program of forall()
// method
  
// Creating object
object GfG
{ 
  
    // Main method
    def main(args:Array[String])
    {
        // Creating a list
        val m1 = List(3, 6, 2, 9, 21)
          
        // Applying forall method
        val result = m1.forall(y => {y % 3 == 0})
          
        // Displays output
        println(result)
      
    }
} 

输出：

false