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# Float80

An extended-precision, floating-point value type.

```
@frozen struct Float80
```

## Overview

`Float80` is available on x86 if the target system’s `long double` C type
is 80-bit, and unavailable otherwise.

## Topics

### Initializers

[`init()`](/documentation/Swift/Float80/init())

[`init?(Substring)`](/documentation/Swift/Float80/init(_:)-2iufm)

[`init?(exactly: Double)`](/documentation/Swift/Float80/init(exactly:)-2szlu)

Creates a new instance initialized to the given value, if it can be
represented without rounding.

[`init?(exactly: Float)`](/documentation/Swift/Float80/init(exactly:)-6kkqt)

Creates a new instance initialized to the given value, if it can be
represented without rounding.

[`init?(exactly: Float80)`](/documentation/Swift/Float80/init(exactly:)-7ol5e)

Creates a new instance initialized to the given value, if it can be
represented without rounding.

[`init(nan: Float80.RawSignificand, signaling: Bool)`](/documentation/Swift/Float80/init(nan:signaling:))

Creates a NaN (“not a number”) value with the specified payload.

### Default Implementations

[AdditiveArithmetic Implementations](/documentation/Swift/Float80/AdditiveArithmetic-Implementations)

[BinaryFloatingPoint Implementations](/documentation/Swift/Float80/BinaryFloatingPoint-Implementations)

[Comparable Implementations](/documentation/Swift/Float80/Comparable-Implementations)

[CustomDebugStringConvertible Implementations](/documentation/Swift/Float80/CustomDebugStringConvertible-Implementations)

[CustomReflectable Implementations](/documentation/Swift/Float80/CustomReflectable-Implementations)

[CustomStringConvertible Implementations](/documentation/Swift/Float80/CustomStringConvertible-Implementations)

[Equatable Implementations](/documentation/Swift/Float80/Equatable-Implementations)

[ExpressibleByFloatLiteral Implementations](/documentation/Swift/Float80/ExpressibleByFloatLiteral-Implementations)

[ExpressibleByIntegerLiteral Implementations](/documentation/Swift/Float80/ExpressibleByIntegerLiteral-Implementations)

[FloatingPoint Implementations](/documentation/Swift/Float80/FloatingPoint-Implementations)

[Hashable Implementations](/documentation/Swift/Float80/Hashable-Implementations)

[LosslessStringConvertible Implementations](/documentation/Swift/Float80/LosslessStringConvertible-Implementations)

[Numeric Implementations](/documentation/Swift/Float80/Numeric-Implementations)

[SignedNumeric Implementations](/documentation/Swift/Float80/SignedNumeric-Implementations)

[Strideable Implementations](/documentation/Swift/Float80/Strideable-Implementations)

[TextOutputStreamable Implementations](/documentation/Swift/Float80/TextOutputStreamable-Implementations)

## Relationships

### Conforms To

[`SignedNumeric`](/documentation/Swift/SignedNumeric)

[`LosslessStringConvertible`](/documentation/Swift/LosslessStringConvertible)

[`FloatingPoint`](/documentation/Swift/FloatingPoint)

[`CVarArg`](/documentation/Swift/CVarArg)

[`BinaryFloatingPoint`](/documentation/Swift/BinaryFloatingPoint)

[`Copyable`](/documentation/Swift/Copyable)

[`Escapable`](/documentation/Swift/Escapable)

[`ConvertibleFromBytes`](/documentation/Swift/ConvertibleFromBytes)

[`CustomStringConvertible`](/documentation/Swift/CustomStringConvertible)

[`BitwiseCopyable`](/documentation/Swift/BitwiseCopyable)

[`Numeric`](/documentation/Swift/Numeric)

[`AdditiveArithmetic`](/documentation/Swift/AdditiveArithmetic)

[`Comparable`](/documentation/Swift/Comparable)

[`TextOutputStreamable`](/documentation/Swift/TextOutputStreamable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`CustomReflectable`](/documentation/Swift/CustomReflectable)

[`Sendable`](/documentation/Swift/Sendable)

[`ExpressibleByFloatLiteral`](/documentation/Swift/ExpressibleByFloatLiteral)

[`Strideable`](/documentation/Swift/Strideable)

[`Equatable`](/documentation/Swift/Equatable)

[`ExpressibleByIntegerLiteral`](/documentation/Swift/ExpressibleByIntegerLiteral)

[`CustomDebugStringConvertible`](/documentation/Swift/CustomDebugStringConvertible)

[`Hashable`](/documentation/Swift/Hashable)

---

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