Professional F# 2.0

Chapter 3. Primitive Types

WHAT'S IN THIS CHAPTER?

• Understanding primitive types

• Declaring primitive type instances

• Applying operators

Like all languages that run on top of the CLR, the F# language provides a core set of primitive types that offer basic integer and floating-point arithmetic capabilities, character string support, Boolean types, and so on. In general, these map to the corresponding CLS types (System.Int16, System.Int32, and so on), as described next, but a few types are new to F# and come from the F# libraries. These types are fully accessible to other languages, such as C# and Visual Basic but obviously have no native language support there and need to be used as any other .NET type is (that is, via fully qualified type names).

BOOLEAN

Probably the simplest primitive type in F# is the bool type, which corresponds to the CLR's underlying System.Boolean type, and has two possible values, true and false.

Booleans support the usual range of logical operations, including && (logical AND) and || (logical OR), and otherwise behave just as Boolean values do in any other .NET language.

NUMERIC TYPES

F# supports a wide range of numeric types, 8 bits in size to 64, in both signed and unsigned versions, as shown here:

TYPE	DESCRIPTION	.NET NAME	LITERALS
Byte	8-bit unsigned integer	System.Byte	3uy, 0xFuy
Sbyte	8-bit signed integer	System.SByte	3y, 0xFy
int16	16-bit signed integer	System.Int16	3s, 0xFs
uint16	16-bi unsigned integer	System.UInt16	3us, 0xFus
int, int32	32-bit signed integer	System.Int32	3, 0xF ...