Sum values of properties inside array of custom objects using reduce

Question

I have following model

class Foo {
var value: Double
var color: UIColor

init?(value: Double, color: UIColor) {
    self.value = value
    self.color = color
  }
}

How can I sum all value property inside of [Foo] using reduce?

Nirav D · Accepted Answer · 2017-05-11 09:38:38Z

54

It simply like this

let sum = array.reduce(0) { $0 + $1.value }

answered May 11, 2017 at 9:38

Nirav D

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Comments

Sulthan · Accepted Answer · 2019-06-27 16:33:36Z

9

The same way as with plain numbers:

let foos: [Foo] = ...
let sum = foos.lazy.map { $0.value }.reduce(0, +)

answered May 11, 2017 at 9:38

Sulthan

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