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Goalchemy

std/unicode/utf8

import "github.com/eugenioenko/goalchemy/std/unicode/utf8"

Package utf8 encodes and decodes UTF-8 text.

const (
  RuneError = '�'
  RuneSelf  = 0x80
  MaxRune   = '\U0010FFFF'
  UTFMax    = 4
)

AppendRune

Section titled “AppendRune”
func AppendRune(p []byte, r rune) []byte

AppendRune appends the UTF-8 encoding of r to p. Invalid runes encode as RuneError.

DecodeLastRune

Section titled “DecodeLastRune”
func DecodeLastRune(p []byte) (rune, int)

DecodeLastRune unpacks the last UTF-8 encoding in p.

DecodeLastRuneInString

Section titled “DecodeLastRuneInString”
func DecodeLastRuneInString(s string) (rune, int)

DecodeLastRuneInString is like DecodeLastRune but its input is a string.

DecodeRune

Section titled “DecodeRune”
func DecodeRune(p []byte) (rune, int)

DecodeRune unpacks the first UTF-8 encoding in p and returns the rune and its width in bytes. It returns (RuneError, 0) for empty input and (RuneError, 1) for an invalid encoding.

DecodeRuneInString

Section titled “DecodeRuneInString”
func DecodeRuneInString(s string) (rune, int)

DecodeRuneInString is like DecodeRune but its input is a string.

EncodeRune

Section titled “EncodeRune”
func EncodeRune(p []byte, r rune) int

EncodeRune writes the UTF-8 encoding of r into p, which must be large enough, and returns the number of bytes written.

FullRune

Section titled “FullRune”
func FullRune(p []byte) bool

FullRune reports whether the bytes in p begin with a full UTF-8 encoding of a rune. An invalid encoding is considered a full rune since it will convert as a width-1 error rune.

FullRuneInString

Section titled “FullRuneInString”
func FullRuneInString(s string) bool

FullRuneInString is like FullRune but its input is a string.

RuneCount

Section titled “RuneCount”
func RuneCount(p []byte) int

RuneCount returns the number of runes in p, counting each invalid byte as one rune.

RuneCountInString

Section titled “RuneCountInString”
func RuneCountInString(s string) int

RuneCountInString is like RuneCount but its input is a string.

RuneLen

Section titled “RuneLen”
func RuneLen(r rune) int

RuneLen returns the number of bytes needed to encode r, or -1 if r is not a valid Unicode scalar value.

RuneStart

Section titled “RuneStart”
func RuneStart(b byte) bool

RuneStart reports whether b could be the first byte of an encoded rune.

Valid

Section titled “Valid”
func Valid(p []byte) bool

Valid reports whether p consists entirely of valid UTF-8 encodings.

ValidRune

Section titled “ValidRune”
func ValidRune(r rune) bool

ValidRune reports whether r can be legally encoded as UTF-8.

ValidString

Section titled “ValidString”
func ValidString(s string) bool

ValidString reports whether s consists entirely of valid UTF-8 encodings.