package bytes

Import Path
	bytes (on go.dev)

Dependency Relation
	imports 6 packages, and imported by 69 packages

Involved Source Files buffer.go Package bytes implements functions for the manipulation of byte slices. It is analogous to the facilities of the [strings] package. reader.go
Code Examples package main import ( "bytes" "fmt" "os" ) func main() { var b bytes.Buffer // A Buffer needs no initialization. b.Write([]byte("Hello ")) fmt.Fprintf(&b, "world!") b.WriteTo(os.Stdout) } package main import ( "bytes" "os" "strconv" ) func main() { var buf bytes.Buffer for i := 0; i < 4; i++ { b := buf.AvailableBuffer() b = strconv.AppendInt(b, int64(i), 10) b = append(b, ' ') buf.Write(b) } os.Stdout.Write(buf.Bytes()) } package main import ( "bytes" "os" ) func main() { buf := bytes.Buffer{} buf.Write([]byte{'h', 'e', 'l', 'l', 'o', ' ', 'w', 'o', 'r', 'l', 'd'}) os.Stdout.Write(buf.Bytes()) } package main import ( "bytes" "fmt" ) func main() { buf1 := bytes.NewBuffer(make([]byte, 10)) buf2 := bytes.NewBuffer(make([]byte, 0, 10)) fmt.Println(buf1.Cap()) fmt.Println(buf2.Cap()) } package main import ( "bytes" "fmt" ) func main() { var b bytes.Buffer b.Grow(64) bb := b.Bytes() b.Write([]byte("64 bytes or fewer")) fmt.Printf("%q", bb[:b.Len()]) } package main import ( "bytes" "fmt" ) func main() { var b bytes.Buffer b.Grow(64) b.Write([]byte("abcde")) fmt.Printf("%d", b.Len()) } package main import ( "bytes" "fmt" ) func main() { var b bytes.Buffer b.Grow(64) b.Write([]byte("abcde")) fmt.Printf("%s\n", b.Next(2)) fmt.Printf("%s\n", b.Next(2)) fmt.Printf("%s", b.Next(2)) } package main import ( "bytes" "fmt" ) func main() { var b bytes.Buffer b.Grow(64) b.Write([]byte("abcde")) rdbuf := make([]byte, 1) n, err := b.Read(rdbuf) if err != nil { panic(err) } fmt.Println(n) fmt.Println(b.String()) fmt.Println(string(rdbuf)) } package main import ( "bytes" "fmt" ) func main() { var b bytes.Buffer b.Grow(64) b.Write([]byte("abcde")) c, err := b.ReadByte() if err != nil { panic(err) } fmt.Println(c) fmt.Println(b.String()) } package main import ( "bytes" "encoding/base64" "io" "os" ) func main() { // A Buffer can turn a string or a []byte into an io.Reader. buf := bytes.NewBufferString("R29waGVycyBydWxlIQ==") dec := base64.NewDecoder(base64.StdEncoding, buf) io.Copy(os.Stdout, dec) } package main import ( "bytes" "fmt" ) func main() { b := []byte("abc") clone := bytes.Clone(b) fmt.Printf("%s\n", clone) clone[0] = 'd' fmt.Printf("%s\n", b) fmt.Printf("%s\n", clone) } package main import ( "bytes" ) func main() { // Interpret Compare's result by comparing it to zero. var a, b []byte if bytes.Compare(a, b) < 0 { // a less b } if bytes.Compare(a, b) <= 0 { // a less or equal b } if bytes.Compare(a, b) > 0 { // a greater b } if bytes.Compare(a, b) >= 0 { // a greater or equal b } // Prefer Equal to Compare for equality comparisons. if bytes.Equal(a, b) { // a equal b } if !bytes.Equal(a, b) { // a not equal b } } package main import ( "bytes" "slices" ) func main() { // Binary search to find a matching byte slice. var needle []byte var haystack [][]byte // Assume sorted _, found := slices.BinarySearchFunc(haystack, needle, bytes.Compare) if found { // Found it! } } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.Contains([]byte("seafood"), []byte("foo"))) fmt.Println(bytes.Contains([]byte("seafood"), []byte("bar"))) fmt.Println(bytes.Contains([]byte("seafood"), []byte(""))) fmt.Println(bytes.Contains([]byte(""), []byte(""))) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.ContainsAny([]byte("I like seafood."), "fÄo!")) fmt.Println(bytes.ContainsAny([]byte("I like seafood."), "去是伟大的.")) fmt.Println(bytes.ContainsAny([]byte("I like seafood."), "")) fmt.Println(bytes.ContainsAny([]byte(""), "")) } package main import ( "bytes" "fmt" ) func main() { f := func(r rune) bool { return r >= 'a' && r <= 'z' } fmt.Println(bytes.ContainsFunc([]byte("HELLO"), f)) fmt.Println(bytes.ContainsFunc([]byte("World"), f)) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.ContainsRune([]byte("I like seafood."), 'f')) fmt.Println(bytes.ContainsRune([]byte("I like seafood."), 'ö')) fmt.Println(bytes.ContainsRune([]byte("去是伟大的!"), '大')) fmt.Println(bytes.ContainsRune([]byte("去是伟大的!"), '!')) fmt.Println(bytes.ContainsRune([]byte(""), '@')) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.Count([]byte("cheese"), []byte("e"))) fmt.Println(bytes.Count([]byte("five"), []byte(""))) // before & after each rune } package main import ( "bytes" "fmt" ) func main() { show := func(s, sep string) { before, after, found := bytes.Cut([]byte(s), []byte(sep)) fmt.Printf("Cut(%q, %q) = %q, %q, %v\n", s, sep, before, after, found) } show("Gopher", "Go") show("Gopher", "ph") show("Gopher", "er") show("Gopher", "Badger") } package main import ( "bytes" "fmt" ) func main() { show := func(s, sep string) { after, found := bytes.CutPrefix([]byte(s), []byte(sep)) fmt.Printf("CutPrefix(%q, %q) = %q, %v\n", s, sep, after, found) } show("Gopher", "Go") show("Gopher", "ph") } package main import ( "bytes" "fmt" ) func main() { show := func(s, sep string) { before, found := bytes.CutSuffix([]byte(s), []byte(sep)) fmt.Printf("CutSuffix(%q, %q) = %q, %v\n", s, sep, before, found) } show("Gopher", "Go") show("Gopher", "er") } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.Equal([]byte("Go"), []byte("Go"))) fmt.Println(bytes.Equal([]byte("Go"), []byte("C++"))) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.EqualFold([]byte("Go"), []byte("go"))) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("Fields are: %q", bytes.Fields([]byte(" foo bar baz "))) } package main import ( "bytes" "fmt" "unicode" ) func main() { f := func(c rune) bool { return !unicode.IsLetter(c) && !unicode.IsNumber(c) } fmt.Printf("Fields are: %q", bytes.FieldsFunc([]byte(" foo1;bar2,baz3..."), f)) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("Go"))) fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("C"))) fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte(""))) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.HasSuffix([]byte("Amigo"), []byte("go"))) fmt.Println(bytes.HasSuffix([]byte("Amigo"), []byte("O"))) fmt.Println(bytes.HasSuffix([]byte("Amigo"), []byte("Ami"))) fmt.Println(bytes.HasSuffix([]byte("Amigo"), []byte(""))) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.Index([]byte("chicken"), []byte("ken"))) fmt.Println(bytes.Index([]byte("chicken"), []byte("dmr"))) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.IndexAny([]byte("chicken"), "aeiouy")) fmt.Println(bytes.IndexAny([]byte("crwth"), "aeiouy")) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.IndexByte([]byte("chicken"), byte('k'))) fmt.Println(bytes.IndexByte([]byte("chicken"), byte('g'))) } package main import ( "bytes" "fmt" "unicode" ) func main() { f := func(c rune) bool { return unicode.Is(unicode.Han, c) } fmt.Println(bytes.IndexFunc([]byte("Hello, 世界"), f)) fmt.Println(bytes.IndexFunc([]byte("Hello, world"), f)) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.IndexRune([]byte("chicken"), 'k')) fmt.Println(bytes.IndexRune([]byte("chicken"), 'd')) } package main import ( "bytes" "fmt" ) func main() { s := [][]byte{[]byte("foo"), []byte("bar"), []byte("baz")} fmt.Printf("%s", bytes.Join(s, []byte(", "))) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.Index([]byte("go gopher"), []byte("go"))) fmt.Println(bytes.LastIndex([]byte("go gopher"), []byte("go"))) fmt.Println(bytes.LastIndex([]byte("go gopher"), []byte("rodent"))) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.LastIndexAny([]byte("go gopher"), "MüQp")) fmt.Println(bytes.LastIndexAny([]byte("go 地鼠"), "地大")) fmt.Println(bytes.LastIndexAny([]byte("go gopher"), "z,!.")) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.LastIndexByte([]byte("go gopher"), byte('g'))) fmt.Println(bytes.LastIndexByte([]byte("go gopher"), byte('r'))) fmt.Println(bytes.LastIndexByte([]byte("go gopher"), byte('z'))) } package main import ( "bytes" "fmt" "unicode" ) func main() { fmt.Println(bytes.LastIndexFunc([]byte("go gopher!"), unicode.IsLetter)) fmt.Println(bytes.LastIndexFunc([]byte("go gopher!"), unicode.IsPunct)) fmt.Println(bytes.LastIndexFunc([]byte("go gopher!"), unicode.IsNumber)) } package main import ( "bytes" "fmt" ) func main() { rot13 := func(r rune) rune { switch { case r >= 'A' && r <= 'Z': return 'A' + (r-'A'+13)%26 case r >= 'a' && r <= 'z': return 'a' + (r-'a'+13)%26 } return r } fmt.Printf("%s\n", bytes.Map(rot13, []byte("'Twas brillig and the slithy gopher..."))) } package main import ( "bytes" "fmt" ) func main() { fmt.Println(bytes.NewReader([]byte("Hi!")).Len()) fmt.Println(bytes.NewReader([]byte("こんにちは!")).Len()) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("ba%s", bytes.Repeat([]byte("na"), 2)) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%s\n", bytes.Replace([]byte("oink oink oink"), []byte("k"), []byte("ky"), 2)) fmt.Printf("%s\n", bytes.Replace([]byte("oink oink oink"), []byte("oink"), []byte("moo"), -1)) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%s\n", bytes.ReplaceAll([]byte("oink oink oink"), []byte("oink"), []byte("moo"))) } package main import ( "bytes" "fmt" ) func main() { rs := bytes.Runes([]byte("go gopher")) for _, r := range rs { fmt.Printf("%#U\n", r) } } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%q\n", bytes.Split([]byte("a,b,c"), []byte(","))) fmt.Printf("%q\n", bytes.Split([]byte("a man a plan a canal panama"), []byte("a "))) fmt.Printf("%q\n", bytes.Split([]byte(" xyz "), []byte(""))) fmt.Printf("%q\n", bytes.Split([]byte(""), []byte("Bernardo O'Higgins"))) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%q\n", bytes.SplitAfter([]byte("a,b,c"), []byte(","))) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%q\n", bytes.SplitAfterN([]byte("a,b,c"), []byte(","), 2)) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%q\n", bytes.SplitN([]byte("a,b,c"), []byte(","), 2)) z := bytes.SplitN([]byte("a,b,c"), []byte(","), 0) fmt.Printf("%q (nil = %v)\n", z, z == nil) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%s", bytes.Title([]byte("her royal highness"))) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%s", bytes.ToLower([]byte("Gopher"))) } package main import ( "bytes" "fmt" "unicode" ) func main() { str := []byte("AHOJ VÝVOJÁRİ GOLANG") totitle := bytes.ToLowerSpecial(unicode.AzeriCase, str) fmt.Println("Original : " + string(str)) fmt.Println("ToLower : " + string(totitle)) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%s\n", bytes.ToTitle([]byte("loud noises"))) fmt.Printf("%s\n", bytes.ToTitle([]byte("хлеб"))) } package main import ( "bytes" "fmt" "unicode" ) func main() { str := []byte("ahoj vývojári golang") totitle := bytes.ToTitleSpecial(unicode.AzeriCase, str) fmt.Println("Original : " + string(str)) fmt.Println("ToTitle : " + string(totitle)) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%s", bytes.ToUpper([]byte("Gopher"))) } package main import ( "bytes" "fmt" "unicode" ) func main() { str := []byte("ahoj vývojári golang") totitle := bytes.ToUpperSpecial(unicode.AzeriCase, str) fmt.Println("Original : " + string(str)) fmt.Println("ToUpper : " + string(totitle)) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%s\n", bytes.ToValidUTF8([]byte("abc"), []byte("\uFFFD"))) fmt.Printf("%s\n", bytes.ToValidUTF8([]byte("a\xffb\xC0\xAFc\xff"), []byte(""))) fmt.Printf("%s\n", bytes.ToValidUTF8([]byte("\xed\xa0\x80"), []byte("abc"))) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("[%q]", bytes.Trim([]byte(" !!! Achtung! Achtung! !!! "), "! ")) } package main import ( "bytes" "fmt" "unicode" ) func main() { fmt.Println(string(bytes.TrimFunc([]byte("go-gopher!"), unicode.IsLetter))) fmt.Println(string(bytes.TrimFunc([]byte("\"go-gopher!\""), unicode.IsLetter))) fmt.Println(string(bytes.TrimFunc([]byte("go-gopher!"), unicode.IsPunct))) fmt.Println(string(bytes.TrimFunc([]byte("1234go-gopher!567"), unicode.IsNumber))) } package main import ( "bytes" "fmt" ) func main() { fmt.Print(string(bytes.TrimLeft([]byte("453gopher8257"), "0123456789"))) } package main import ( "bytes" "fmt" "unicode" ) func main() { fmt.Println(string(bytes.TrimLeftFunc([]byte("go-gopher"), unicode.IsLetter))) fmt.Println(string(bytes.TrimLeftFunc([]byte("go-gopher!"), unicode.IsPunct))) fmt.Println(string(bytes.TrimLeftFunc([]byte("1234go-gopher!567"), unicode.IsNumber))) } package main import ( "bytes" "fmt" ) func main() { var b = []byte("Goodbye,, world!") b = bytes.TrimPrefix(b, []byte("Goodbye,")) b = bytes.TrimPrefix(b, []byte("See ya,")) fmt.Printf("Hello%s", b) } package main import ( "bytes" "fmt" ) func main() { fmt.Print(string(bytes.TrimRight([]byte("453gopher8257"), "0123456789"))) } package main import ( "bytes" "fmt" "unicode" ) func main() { fmt.Println(string(bytes.TrimRightFunc([]byte("go-gopher"), unicode.IsLetter))) fmt.Println(string(bytes.TrimRightFunc([]byte("go-gopher!"), unicode.IsPunct))) fmt.Println(string(bytes.TrimRightFunc([]byte("1234go-gopher!567"), unicode.IsNumber))) } package main import ( "bytes" "fmt" ) func main() { fmt.Printf("%s", bytes.TrimSpace([]byte(" \t\n a lone gopher \n\t\r\n"))) } package main import ( "bytes" "os" ) func main() { var b = []byte("Hello, goodbye, etc!") b = bytes.TrimSuffix(b, []byte("goodbye, etc!")) b = bytes.TrimSuffix(b, []byte("gopher")) b = append(b, bytes.TrimSuffix([]byte("world!"), []byte("x!"))...) os.Stdout.Write(b) }
Package-Level Type Names (total 2)
/* sort by: | */
A Buffer is a variable-sized buffer of bytes with [Buffer.Read] and [Buffer.Write] methods. The zero value for Buffer is an empty buffer ready to use. Available returns how many bytes are unused in the buffer. AvailableBuffer returns an empty buffer with b.Available() capacity. This buffer is intended to be appended to and passed to an immediately succeeding [Buffer.Write] call. The buffer is only valid until the next write operation on b. Bytes returns a slice of length b.Len() holding the unread portion of the buffer. The slice is valid for use only until the next buffer modification (that is, only until the next call to a method like [Buffer.Read], [Buffer.Write], [Buffer.Reset], or [Buffer.Truncate]). The slice aliases the buffer content at least until the next buffer modification, so immediate changes to the slice will affect the result of future reads. Cap returns the capacity of the buffer's underlying byte slice, that is, the total space allocated for the buffer's data. Grow grows the buffer's capacity, if necessary, to guarantee space for another n bytes. After Grow(n), at least n bytes can be written to the buffer without another allocation. If n is negative, Grow will panic. If the buffer can't grow it will panic with [ErrTooLarge]. Len returns the number of bytes of the unread portion of the buffer; b.Len() == len(b.Bytes()). Next returns a slice containing the next n bytes from the buffer, advancing the buffer as if the bytes had been returned by [Buffer.Read]. If there are fewer than n bytes in the buffer, Next returns the entire buffer. The slice is only valid until the next call to a read or write method. Read reads the next len(p) bytes from the buffer or until the buffer is drained. The return value n is the number of bytes read. If the buffer has no data to return, err is io.EOF (unless len(p) is zero); otherwise it is nil. ReadByte reads and returns the next byte from the buffer. If no byte is available, it returns error io.EOF. ReadBytes reads until the first occurrence of delim in the input, returning a slice containing the data up to and including the delimiter. If ReadBytes encounters an error before finding a delimiter, it returns the data read before the error and the error itself (often io.EOF). ReadBytes returns err != nil if and only if the returned data does not end in delim. ReadFrom reads data from r until EOF and appends it to the buffer, growing the buffer as needed. The return value n is the number of bytes read. Any error except io.EOF encountered during the read is also returned. If the buffer becomes too large, ReadFrom will panic with [ErrTooLarge]. ReadRune reads and returns the next UTF-8-encoded Unicode code point from the buffer. If no bytes are available, the error returned is io.EOF. If the bytes are an erroneous UTF-8 encoding, it consumes one byte and returns U+FFFD, 1. ReadString reads until the first occurrence of delim in the input, returning a string containing the data up to and including the delimiter. If ReadString encounters an error before finding a delimiter, it returns the data read before the error and the error itself (often io.EOF). ReadString returns err != nil if and only if the returned data does not end in delim. Reset resets the buffer to be empty, but it retains the underlying storage for use by future writes. Reset is the same as [Buffer.Truncate](0). String returns the contents of the unread portion of the buffer as a string. If the [Buffer] is a nil pointer, it returns "<nil>". To build strings more efficiently, see the strings.Builder type. Truncate discards all but the first n unread bytes from the buffer but continues to use the same allocated storage. It panics if n is negative or greater than the length of the buffer. UnreadByte unreads the last byte returned by the most recent successful read operation that read at least one byte. If a write has happened since the last read, if the last read returned an error, or if the read read zero bytes, UnreadByte returns an error. UnreadRune unreads the last rune returned by [Buffer.ReadRune]. If the most recent read or write operation on the buffer was not a successful [Buffer.ReadRune], UnreadRune returns an error. (In this regard it is stricter than [Buffer.UnreadByte], which will unread the last byte from any read operation.) Write appends the contents of p to the buffer, growing the buffer as needed. The return value n is the length of p; err is always nil. If the buffer becomes too large, Write will panic with [ErrTooLarge]. WriteByte appends the byte c to the buffer, growing the buffer as needed. The returned error is always nil, but is included to match [bufio.Writer]'s WriteByte. If the buffer becomes too large, WriteByte will panic with [ErrTooLarge]. WriteRune appends the UTF-8 encoding of Unicode code point r to the buffer, returning its length and an error, which is always nil but is included to match [bufio.Writer]'s WriteRune. The buffer is grown as needed; if it becomes too large, WriteRune will panic with [ErrTooLarge]. WriteString appends the contents of s to the buffer, growing the buffer as needed. The return value n is the length of s; err is always nil. If the buffer becomes too large, WriteString will panic with [ErrTooLarge]. WriteTo writes data to w until the buffer is drained or an error occurs. The return value n is the number of bytes written; it always fits into an int, but it is int64 to match the io.WriterTo interface. Any error encountered during the write is also returned. *Buffer : compress/flate.Reader *Buffer : expvar.Var *Buffer : fmt.Stringer *Buffer : image/jpeg.Reader *Buffer : internal/bisect.Writer *Buffer : io.ByteReader *Buffer : io.ByteScanner *Buffer : io.ByteWriter *Buffer : io.Reader *Buffer : io.ReaderFrom *Buffer : io.ReadWriter *Buffer : io.RuneReader *Buffer : io.RuneScanner *Buffer : io.StringWriter *Buffer : io.Writer *Buffer : io.WriterTo func NewBuffer(buf []byte) *Buffer func NewBufferString(s string) *Buffer func encoding/json.Compact(dst *Buffer, src []byte) error func encoding/json.HTMLEscape(dst *Buffer, src []byte) func encoding/json.Indent(dst *Buffer, src []byte, prefix, indent string) error func go/types.WriteExpr(buf *Buffer, x ast.Expr) func go/types.WriteSignature(buf *Buffer, sig *types.Signature, qf types.Qualifier) func go/types.WriteType(buf *Buffer, typ types.Type, qf types.Qualifier)
A Reader implements the io.Reader, io.ReaderAt, io.WriterTo, io.Seeker, io.ByteScanner, and io.RuneScanner interfaces by reading from a byte slice. Unlike a [Buffer], a Reader is read-only and supports seeking. The zero value for Reader operates like a Reader of an empty slice. Len returns the number of bytes of the unread portion of the slice. Read implements the [io.Reader] interface. ReadAt implements the [io.ReaderAt] interface. ReadByte implements the [io.ByteReader] interface. ReadRune implements the [io.RuneReader] interface. Reset resets the [Reader] to be reading from b. Seek implements the [io.Seeker] interface. Size returns the original length of the underlying byte slice. Size is the number of bytes available for reading via [Reader.ReadAt]. The result is unaffected by any method calls except [Reader.Reset]. UnreadByte complements [Reader.ReadByte] in implementing the [io.ByteScanner] interface. UnreadRune complements [Reader.ReadRune] in implementing the [io.RuneScanner] interface. WriteTo implements the [io.WriterTo] interface. *Reader : compress/flate.Reader *Reader : image/jpeg.Reader *Reader : io.ByteReader *Reader : io.ByteScanner *Reader : io.Reader *Reader : io.ReaderAt *Reader : io.ReadSeeker *Reader : io.RuneReader *Reader : io.RuneScanner *Reader : io.Seeker *Reader : io.WriterTo func NewReader(b []byte) *Reader
Package-Level Functions (total 55)
Clone returns a copy of b[:len(b)]. The result may have additional unused capacity. Clone(nil) returns nil.
Compare returns an integer comparing two byte slices lexicographically. The result will be 0 if a == b, -1 if a < b, and +1 if a > b. A nil argument is equivalent to an empty slice.
Contains reports whether subslice is within b.
ContainsAny reports whether any of the UTF-8-encoded code points in chars are within b.
ContainsFunc reports whether any of the UTF-8-encoded code points r within b satisfy f(r).
ContainsRune reports whether the rune is contained in the UTF-8-encoded byte slice b.
Count counts the number of non-overlapping instances of sep in s. If sep is an empty slice, Count returns 1 + the number of UTF-8-encoded code points in s.
Cut slices s around the first instance of sep, returning the text before and after sep. The found result reports whether sep appears in s. If sep does not appear in s, cut returns s, nil, false. Cut returns slices of the original slice s, not copies.
CutPrefix returns s without the provided leading prefix byte slice and reports whether it found the prefix. If s doesn't start with prefix, CutPrefix returns s, false. If prefix is the empty byte slice, CutPrefix returns s, true. CutPrefix returns slices of the original slice s, not copies.
CutSuffix returns s without the provided ending suffix byte slice and reports whether it found the suffix. If s doesn't end with suffix, CutSuffix returns s, false. If suffix is the empty byte slice, CutSuffix returns s, true. CutSuffix returns slices of the original slice s, not copies.
Equal reports whether a and b are the same length and contain the same bytes. A nil argument is equivalent to an empty slice.
EqualFold reports whether s and t, interpreted as UTF-8 strings, are equal under simple Unicode case-folding, which is a more general form of case-insensitivity.
Fields interprets s as a sequence of UTF-8-encoded code points. It splits the slice s around each instance of one or more consecutive white space characters, as defined by unicode.IsSpace, returning a slice of subslices of s or an empty slice if s contains only white space.
FieldsFunc interprets s as a sequence of UTF-8-encoded code points. It splits the slice s at each run of code points c satisfying f(c) and returns a slice of subslices of s. If all code points in s satisfy f(c), or len(s) == 0, an empty slice is returned. FieldsFunc makes no guarantees about the order in which it calls f(c) and assumes that f always returns the same value for a given c.
HasPrefix reports whether the byte slice s begins with prefix.
HasSuffix reports whether the byte slice s ends with suffix.
Index returns the index of the first instance of sep in s, or -1 if sep is not present in s.
IndexAny interprets s as a sequence of UTF-8-encoded Unicode code points. It returns the byte index of the first occurrence in s of any of the Unicode code points in chars. It returns -1 if chars is empty or if there is no code point in common.
IndexByte returns the index of the first instance of c in b, or -1 if c is not present in b.
IndexFunc interprets s as a sequence of UTF-8-encoded code points. It returns the byte index in s of the first Unicode code point satisfying f(c), or -1 if none do.
IndexRune interprets s as a sequence of UTF-8-encoded code points. It returns the byte index of the first occurrence in s of the given rune. It returns -1 if rune is not present in s. If r is utf8.RuneError, it returns the first instance of any invalid UTF-8 byte sequence.
Join concatenates the elements of s to create a new byte slice. The separator sep is placed between elements in the resulting slice.
LastIndex returns the index of the last instance of sep in s, or -1 if sep is not present in s.
LastIndexAny interprets s as a sequence of UTF-8-encoded Unicode code points. It returns the byte index of the last occurrence in s of any of the Unicode code points in chars. It returns -1 if chars is empty or if there is no code point in common.
LastIndexByte returns the index of the last instance of c in s, or -1 if c is not present in s.
LastIndexFunc interprets s as a sequence of UTF-8-encoded code points. It returns the byte index in s of the last Unicode code point satisfying f(c), or -1 if none do.
Map returns a copy of the byte slice s with all its characters modified according to the mapping function. If mapping returns a negative value, the character is dropped from the byte slice with no replacement. The characters in s and the output are interpreted as UTF-8-encoded code points.
NewBuffer creates and initializes a new [Buffer] using buf as its initial contents. The new [Buffer] takes ownership of buf, and the caller should not use buf after this call. NewBuffer is intended to prepare a [Buffer] to read existing data. It can also be used to set the initial size of the internal buffer for writing. To do that, buf should have the desired capacity but a length of zero. In most cases, new([Buffer]) (or just declaring a [Buffer] variable) is sufficient to initialize a [Buffer].
NewBufferString creates and initializes a new [Buffer] using string s as its initial contents. It is intended to prepare a buffer to read an existing string. In most cases, new([Buffer]) (or just declaring a [Buffer] variable) is sufficient to initialize a [Buffer].
NewReader returns a new [Reader] reading from b.
Repeat returns a new byte slice consisting of count copies of b. It panics if count is negative or if the result of (len(b) * count) overflows.
Replace returns a copy of the slice s with the first n non-overlapping instances of old replaced by new. If old is empty, it matches at the beginning of the slice and after each UTF-8 sequence, yielding up to k+1 replacements for a k-rune slice. If n < 0, there is no limit on the number of replacements.
ReplaceAll returns a copy of the slice s with all non-overlapping instances of old replaced by new. If old is empty, it matches at the beginning of the slice and after each UTF-8 sequence, yielding up to k+1 replacements for a k-rune slice.
Runes interprets s as a sequence of UTF-8-encoded code points. It returns a slice of runes (Unicode code points) equivalent to s.
Split slices s into all subslices separated by sep and returns a slice of the subslices between those separators. If sep is empty, Split splits after each UTF-8 sequence. It is equivalent to SplitN with a count of -1. To split around the first instance of a separator, see Cut.
SplitAfter slices s into all subslices after each instance of sep and returns a slice of those subslices. If sep is empty, SplitAfter splits after each UTF-8 sequence. It is equivalent to SplitAfterN with a count of -1.
SplitAfterN slices s into subslices after each instance of sep and returns a slice of those subslices. If sep is empty, SplitAfterN splits after each UTF-8 sequence. The count determines the number of subslices to return: n > 0: at most n subslices; the last subslice will be the unsplit remainder. n == 0: the result is nil (zero subslices) n < 0: all subslices
SplitN slices s into subslices separated by sep and returns a slice of the subslices between those separators. If sep is empty, SplitN splits after each UTF-8 sequence. The count determines the number of subslices to return: n > 0: at most n subslices; the last subslice will be the unsplit remainder. n == 0: the result is nil (zero subslices) n < 0: all subslices To split around the first instance of a separator, see Cut.
Title treats s as UTF-8-encoded bytes and returns a copy with all Unicode letters that begin words mapped to their title case. Deprecated: The rule Title uses for word boundaries does not handle Unicode punctuation properly. Use golang.org/x/text/cases instead.
ToLower returns a copy of the byte slice s with all Unicode letters mapped to their lower case.
ToLowerSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their lower case, giving priority to the special casing rules.
ToTitle treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their title case.
ToTitleSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their title case, giving priority to the special casing rules.
ToUpper returns a copy of the byte slice s with all Unicode letters mapped to their upper case.
ToUpperSpecial treats s as UTF-8-encoded bytes and returns a copy with all the Unicode letters mapped to their upper case, giving priority to the special casing rules.
ToValidUTF8 treats s as UTF-8-encoded bytes and returns a copy with each run of bytes representing invalid UTF-8 replaced with the bytes in replacement, which may be empty.
Trim returns a subslice of s by slicing off all leading and trailing UTF-8-encoded code points contained in cutset.
TrimFunc returns a subslice of s by slicing off all leading and trailing UTF-8-encoded code points c that satisfy f(c).
TrimLeft returns a subslice of s by slicing off all leading UTF-8-encoded code points contained in cutset.
TrimLeftFunc treats s as UTF-8-encoded bytes and returns a subslice of s by slicing off all leading UTF-8-encoded code points c that satisfy f(c).
TrimPrefix returns s without the provided leading prefix string. If s doesn't start with prefix, s is returned unchanged.
TrimRight returns a subslice of s by slicing off all trailing UTF-8-encoded code points that are contained in cutset.
TrimRightFunc returns a subslice of s by slicing off all trailing UTF-8-encoded code points c that satisfy f(c).
TrimSpace returns a subslice of s by slicing off all leading and trailing white space, as defined by Unicode.
TrimSuffix returns s without the provided trailing suffix string. If s doesn't end with suffix, s is returned unchanged.
Package-Level Variables (only one)
ErrTooLarge is passed to panic if memory cannot be allocated to store data in a buffer.
Package-Level Constants (only one)
MinRead is the minimum slice size passed to a Read call by [Buffer.ReadFrom]. As long as the [Buffer] has at least MinRead bytes beyond what is required to hold the contents of r, ReadFrom will not grow the underlying buffer.