Scala's in-depth combat classic 85th: the powerful expressive combat of the for expression in Scala

High-order function filter Source analysis

Package Com.dt.scala.forexpression

Case class Person (name:string, Ismale:boolean, children:person*)

Object For_expressive {

def main (args:array[string]) {

Val Lauren = person ("Lauren", false)

Val Rocky = person ("Rocky", True)

Val Vivian = person ("Vivian", False, Lauren, Rocky)

Val persons = List (Lauren, Rocky, Vivian)

Val result = Persons filter (person =!person.ismale) FlatMap (person =

(Person.children map (child = (Person.name, child.name)))

println (Result)

Val Forresult = for (person <-persons, if!person.ismale; child <-Person.children)

Yield (Person.name, child.name)

println (Forresult)

}

}

FlatMap, flattening, is the merging of 2 sets.

The functions in the example can be implemented with a for loop, and the expressive force is clearer.

Behind the For loop is the Flatmap way, and the jump code can see Flatmap directly. Powerful features.

Scala's in-depth combat classic 85th: the powerful expressive combat of the for expression in Scala