func Gen(w io.Writer, x interface{}, c *Config) error
Gen generates code for unpacking integers created with 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.
Config determines settings for packing and generation. If a Config is used, the same Config should be used for packing and generation.
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
}