---
title: "+(_:_:)"
framework: swift
role: symbol
role_heading: Operator
path: "swift/uint128/+(_:_:)"
---

# +(_:_:)

Adds two values and produces their sum.

## Declaration

```swift
static func + (a: UInt128, b: UInt128) -> UInt128
```

## Discussion

Discussion The addition operator (+) calculates the sum of its two arguments. For example: 1 + 2                   // 3 -10 + 15                // 5 -15 + -5                // -20 21.5 + 3.25             // 24.75 You cannot use + with arguments of different types. To add values of different types, convert one of the values to the other value’s type. let x: Int8 = 21 let y: Int = 1000000 Int(x) + y              // 1000021