Using a filter map

Question

Using a filter map

I want to loop over an array of arrays to find a specific element and return true if exited.

var fruits = ["apple", "banana"]
var names = ["ivan", "john", "maria"]
var mainArray = [fruits, names]

// i want to return true if theres a name/fruit that is "john"
func search() -> Bool {
    for object in mainArray {
        if (object.filter { $0 == "john" }).count > 0 {
           return true
        }
    }
    return false
}


search()

This works, but is there a shorter version using .map and an exception for the object in mainArray? how is mainArray.map.filter ...?

+3

swift

Godfather 03 jul. 15 at 10:14

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2 answers

I know this doesn't use a map and a filter, but why don't you?

func search() -> Bool {
    for object in mainArray {
        if contains(object, "john") {
           return true
        }
    }
    return false
}

0

The tom 03 jul. 15 at 10:19

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oisdk · Accepted Answer · 2015-07-03T10:18:12+0000

var fruits = ["apple", "banana"]
var names = ["ivan", "john", "maria"]
var mainArray = [fruits, names]

func search() -> Bool {
  return mainArray.contains { $0.contains("john") }
}

Or in Swift 1:

func search() -> Bool {
  return contains(mainArray) {
    inner in contains(inner) {
      $0 == "john"
    }
  }
}

As @AirspeedVelocity pointed out, you can actually make these closures have shorthand arguments:

func search() -> Bool {
  return contains(mainArray) { contains($0) { $0 == "john" } }
}

Using a filter map

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