---
title: "-(_:)"
framework: swift
role: symbol
role_heading: Operator
path: "swift/float80/-(_:)-37tqf"
---

# -(_:)

Returns the additive inverse of the specified value.

## Declaration

```swift
static func - (operand: Self) -> Self
```

## Return Value

Return Value The additive inverse of this value.

## Discussion

Discussion The negation operator (prefix -) returns the additive inverse of its argument. let x = 21 let y = -x // y == -21 The resulting value must be representable in the same type as the argument. In particular, negating a signed, fixed-width integer type’s minimum results in a value that cannot be represented. let z = -Int8.min // Overflow error