bitfield

Documentation

Overview

Package bitfield converts annotated structs into integer values.

Any field that is marked with a bitfield tag is compacted. The tag value has two parts. The part before the comma determines the method name for a generated type. If left blank the name of the field is used. The part after the comma determines the number of bits to use for the representation.

Index

• func Gen(w io.Writer, x interface{}, c *Config) error
• func Pack(x interface{}, c *Config) (packed uint64, err error)
• type Config

Functions

func Gen

func Gen(w io.Writer, x interface{}, c *Config) error

Gen generates code for unpacking integers created with Pack.

func Pack

func Pack(x interface{}, c *Config) (packed uint64, err error)

Pack packs annotated bit ranges of struct x in an integer.

Only fields that have a "bitfield" tag are compacted.

Types

type Config

type Config struct {
	// NumBits fixes the maximum allowed bits for the integer representation.
	// If NumBits is not 8, 16, 32, or 64, the actual underlying integer size
	// will be the next largest available.
	NumBits uint

	// If Package is set, code generation will write a package clause.
	Package string

	// TypeName is the name for the generated type. By default it is the name
	// of the type of the value passed to Gen.
	TypeName string
}

Config determines settings for packing and generation. If a Config is used, the same Config should be used for packing and generation.