Adds unmodified source files from golang.org.

third_party/golang/src/fmt/print.go

Index: third_party/golang/src/fmt/print.go
diff --git a/third_party/golang/src/fmt/print.go b/third_party/golang/src/fmt/print.go
new file mode 100644
index 0000000000000000000000000000000000000000..a84375b25e9161588d259a5da1b4805dc11971ed
--- /dev/null
+++ b/third_party/golang/src/fmt/print.go
@@ -0,0 +1,1259 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package fmt
+
+import (
+	"errors"
+	"io"
+	"os"
+	"reflect"
+	"sync"
+	"unicode/utf8"
+)
+
+// Some constants in the form of bytes, to avoid string overhead.
+// Needlessly fastidious, I suppose.
+var (
+	commaSpaceBytes  = []byte(", ")
+	nilAngleBytes    = []byte("<nil>")
+	nilParenBytes    = []byte("(nil)")
+	nilBytes         = []byte("nil")
+	mapBytes         = []byte("map[")
+	percentBangBytes = []byte("%!")
+	missingBytes     = []byte("(MISSING)")
+	badIndexBytes    = []byte("(BADINDEX)")
+	panicBytes       = []byte("(PANIC=")
+	extraBytes       = []byte("%!(EXTRA ")
+	irparenBytes     = []byte("i)")
+	bytesBytes       = []byte("[]byte{")
+	badWidthBytes    = []byte("%!(BADWIDTH)")
+	badPrecBytes     = []byte("%!(BADPREC)")
+	noVerbBytes      = []byte("%!(NOVERB)")
+)
+
+// State represents the printer state passed to custom formatters.
+// It provides access to the io.Writer interface plus information about
+// the flags and options for the operand's format specifier.
+type State interface {
+	// Write is the function to call to emit formatted output to be printed.
+	Write(b []byte) (ret int, err error)
+	// Width returns the value of the width option and whether it has been set.
+	Width() (wid int, ok bool)
+	// Precision returns the value of the precision option and whether it has been set.
+	Precision() (prec int, ok bool)
+
+	// Flag reports whether the flag c, a character, has been set.
+	Flag(c int) bool
+}
+
+// Formatter is the interface implemented by values with a custom formatter.
+// The implementation of Format may call Sprint(f) or Fprint(f) etc.
+// to generate its output.
+type Formatter interface {
+	Format(f State, c rune)
+}
+
+// Stringer is implemented by any value that has a String method,
+// which defines the ``native'' format for that value.
+// The String method is used to print values passed as an operand
+// to any format that accepts a string or to an unformatted printer
+// such as Print.
+type Stringer interface {
+	String() string
+}
+
+// GoStringer is implemented by any value that has a GoString method,
+// which defines the Go syntax for that value.
+// The GoString method is used to print values passed as an operand
+// to a %#v format.
+type GoStringer interface {
+	GoString() string
+}
+
+// Use simple []byte instead of bytes.Buffer to avoid large dependency.
+type buffer []byte
+
+func (b *buffer) Write(p []byte) (n int, err error) {
+	*b = append(*b, p...)
+	return len(p), nil
+}
+
+func (b *buffer) WriteString(s string) (n int, err error) {
+	*b = append(*b, s...)
+	return len(s), nil
+}
+
+func (b *buffer) WriteByte(c byte) error {
+	*b = append(*b, c)
+	return nil
+}
+
+func (bp *buffer) WriteRune(r rune) error {
+	if r < utf8.RuneSelf {
+		*bp = append(*bp, byte(r))
+		return nil
+	}
+
+	b := *bp
+	n := len(b)
+	for n+utf8.UTFMax > cap(b) {
+		b = append(b, 0)
+	}
+	w := utf8.EncodeRune(b[n:n+utf8.UTFMax], r)
+	*bp = b[:n+w]
+	return nil
+}
+
+type pp struct {
+	n         int
+	panicking bool
+	erroring  bool // printing an error condition
+	buf       buffer
+	// arg holds the current item, as an interface{}.
+	arg interface{}
+	// value holds the current item, as a reflect.Value, and will be
+	// the zero Value if the item has not been reflected.
+	value reflect.Value
+	// reordered records whether the format string used argument reordering.
+	reordered bool
+	// goodArgNum records whether the most recent reordering directive was valid.
+	goodArgNum bool
+	runeBuf    [utf8.UTFMax]byte
+	fmt        fmt
+}
+
+var ppFree = sync.Pool{
+	New: func() interface{} { return new(pp) },
+}
+
+// newPrinter allocates a new pp struct or grabs a cached one.
+func newPrinter() *pp {
+	p := ppFree.Get().(*pp)
+	p.panicking = false
+	p.erroring = false
+	p.fmt.init(&p.buf)
+	return p
+}
+
+// free saves used pp structs in ppFree; avoids an allocation per invocation.
+func (p *pp) free() {
+	// Don't hold on to pp structs with large buffers.
+	if cap(p.buf) > 1024 {
+		return
+	}
+	p.buf = p.buf[:0]
+	p.arg = nil
+	p.value = reflect.Value{}
+	ppFree.Put(p)
+}
+
+func (p *pp) Width() (wid int, ok bool) { return p.fmt.wid, p.fmt.widPresent }
+
+func (p *pp) Precision() (prec int, ok bool) { return p.fmt.prec, p.fmt.precPresent }
+
+func (p *pp) Flag(b int) bool {
+	switch b {
+	case '-':
+		return p.fmt.minus
+	case '+':
+		return p.fmt.plus
+	case '#':
+		return p.fmt.sharp
+	case ' ':
+		return p.fmt.space
+	case '0':
+		return p.fmt.zero
+	}
+	return false
+}
+
+func (p *pp) add(c rune) {
+	p.buf.WriteRune(c)
+}
+
+// Implement Write so we can call Fprintf on a pp (through State), for
+// recursive use in custom verbs.
+func (p *pp) Write(b []byte) (ret int, err error) {
+	return p.buf.Write(b)
+}
+
+// These routines end in 'f' and take a format string.
+
+// Fprintf formats according to a format specifier and writes to w.
+// It returns the number of bytes written and any write error encountered.
+func Fprintf(w io.Writer, format string, a ...interface{}) (n int, err error) {
+	p := newPrinter()
+	p.doPrintf(format, a)
+	n, err = w.Write(p.buf)
+	p.free()
+	return
+}
+
+// Printf formats according to a format specifier and writes to standard output.
+// It returns the number of bytes written and any write error encountered.
+func Printf(format string, a ...interface{}) (n int, err error) {
+	return Fprintf(os.Stdout, format, a...)
+}
+
+// Sprintf formats according to a format specifier and returns the resulting string.
+func Sprintf(format string, a ...interface{}) string {
+	p := newPrinter()
+	p.doPrintf(format, a)
+	s := string(p.buf)
+	p.free()
+	return s
+}
+
+// Errorf formats according to a format specifier and returns the string
+// as a value that satisfies error.
+func Errorf(format string, a ...interface{}) error {
+	return errors.New(Sprintf(format, a...))
+}
+
+// These routines do not take a format string
+
+// Fprint formats using the default formats for its operands and writes to w.
+// Spaces are added between operands when neither is a string.
+// It returns the number of bytes written and any write error encountered.
+func Fprint(w io.Writer, a ...interface{}) (n int, err error) {
+	p := newPrinter()
+	p.doPrint(a, false, false)
+	n, err = w.Write(p.buf)
+	p.free()
+	return
+}
+
+// Print formats using the default formats for its operands and writes to standard output.
+// Spaces are added between operands when neither is a string.
+// It returns the number of bytes written and any write error encountered.
+func Print(a ...interface{}) (n int, err error) {
+	return Fprint(os.Stdout, a...)
+}
+
+// Sprint formats using the default formats for its operands and returns the resulting string.
+// Spaces are added between operands when neither is a string.
+func Sprint(a ...interface{}) string {
+	p := newPrinter()
+	p.doPrint(a, false, false)
+	s := string(p.buf)
+	p.free()
+	return s
+}
+
+// These routines end in 'ln', do not take a format string,
+// always add spaces between operands, and add a newline
+// after the last operand.
+
+// Fprintln formats using the default formats for its operands and writes to w.
+// Spaces are always added between operands and a newline is appended.
+// It returns the number of bytes written and any write error encountered.
+func Fprintln(w io.Writer, a ...interface{}) (n int, err error) {
+	p := newPrinter()
+	p.doPrint(a, true, true)
+	n, err = w.Write(p.buf)
+	p.free()
+	return
+}
+
+// Println formats using the default formats for its operands and writes to standard output.
+// Spaces are always added between operands and a newline is appended.
+// It returns the number of bytes written and any write error encountered.
+func Println(a ...interface{}) (n int, err error) {
+	return Fprintln(os.Stdout, a...)
+}
+
+// Sprintln formats using the default formats for its operands and returns the resulting string.
+// Spaces are always added between operands and a newline is appended.
+func Sprintln(a ...interface{}) string {
+	p := newPrinter()
+	p.doPrint(a, true, true)
+	s := string(p.buf)
+	p.free()
+	return s
+}
+
+// getField gets the i'th field of the struct value.
+// If the field is itself is an interface, return a value for
+// the thing inside the interface, not the interface itself.
+func getField(v reflect.Value, i int) reflect.Value {
+	val := v.Field(i)
+	if val.Kind() == reflect.Interface && !val.IsNil() {
+		val = val.Elem()
+	}
+	return val
+}
+
+// tooLarge reports whether the magnitude of the integer is
+// too large to be used as a formatting width or precision.
+func tooLarge(x int) bool {
+	const max int = 1e6
+	return x > max || x < -max
+}
+
+// parsenum converts ASCII to integer.  num is 0 (and isnum is false) if no number present.
+func parsenum(s string, start, end int) (num int, isnum bool, newi int) {
+	if start >= end {
+		return 0, false, end
+	}
+	for newi = start; newi < end && '0' <= s[newi] && s[newi] <= '9'; newi++ {
+		if tooLarge(num) {
+			return 0, false, end // Overflow; crazy long number most likely.
+		}
+		num = num*10 + int(s[newi]-'0')
+		isnum = true
+	}
+	return
+}
+
+func (p *pp) unknownType(v reflect.Value) {
+	if !v.IsValid() {
+		p.buf.Write(nilAngleBytes)
+		return
+	}
+	p.buf.WriteByte('?')
+	p.buf.WriteString(v.Type().String())
+	p.buf.WriteByte('?')
+}
+
+func (p *pp) badVerb(verb rune) {
+	p.erroring = true
+	p.add('%')
+	p.add('!')
+	p.add(verb)
+	p.add('(')
+	switch {
+	case p.arg != nil:
+		p.buf.WriteString(reflect.TypeOf(p.arg).String())
+		p.add('=')
+		p.printArg(p.arg, 'v', 0)
+	case p.value.IsValid():
+		p.buf.WriteString(p.value.Type().String())
+		p.add('=')
+		p.printValue(p.value, 'v', 0)
+	default:
+		p.buf.Write(nilAngleBytes)
+	}
+	p.add(')')
+	p.erroring = false
+}
+
+func (p *pp) fmtBool(v bool, verb rune) {
+	switch verb {
+	case 't', 'v':
+		p.fmt.fmt_boolean(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+// fmtC formats a rune for the 'c' format.
+func (p *pp) fmtC(c int64) {
+	r := rune(c) // Check for overflow.
+	if int64(r) != c {
+		r = utf8.RuneError
+	}
+	w := utf8.EncodeRune(p.runeBuf[0:utf8.UTFMax], r)
+	p.fmt.pad(p.runeBuf[0:w])
+}
+
+func (p *pp) fmtInt64(v int64, verb rune) {
+	switch verb {
+	case 'b':
+		p.fmt.integer(v, 2, signed, ldigits)
+	case 'c':
+		p.fmtC(v)
+	case 'd', 'v':
+		p.fmt.integer(v, 10, signed, ldigits)
+	case 'o':
+		p.fmt.integer(v, 8, signed, ldigits)
+	case 'q':
+		if 0 <= v && v <= utf8.MaxRune {
+			p.fmt.fmt_qc(v)
+		} else {
+			p.badVerb(verb)
+		}
+	case 'x':
+		p.fmt.integer(v, 16, signed, ldigits)
+	case 'U':
+		p.fmtUnicode(v)
+	case 'X':
+		p.fmt.integer(v, 16, signed, udigits)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+// fmt0x64 formats a uint64 in hexadecimal and prefixes it with 0x or
+// not, as requested, by temporarily setting the sharp flag.
+func (p *pp) fmt0x64(v uint64, leading0x bool) {
+	sharp := p.fmt.sharp
+	p.fmt.sharp = leading0x
+	p.fmt.integer(int64(v), 16, unsigned, ldigits)
+	p.fmt.sharp = sharp
+}
+
+// fmtUnicode formats a uint64 in U+1234 form by
+// temporarily turning on the unicode flag and tweaking the precision.
+func (p *pp) fmtUnicode(v int64) {
+	precPresent := p.fmt.precPresent
+	sharp := p.fmt.sharp
+	p.fmt.sharp = false
+	prec := p.fmt.prec
+	if !precPresent {
+		// If prec is already set, leave it alone; otherwise 4 is minimum.
+		p.fmt.prec = 4
+		p.fmt.precPresent = true
+	}
+	p.fmt.unicode = true // turn on U+
+	p.fmt.uniQuote = sharp
+	p.fmt.integer(int64(v), 16, unsigned, udigits)
+	p.fmt.unicode = false
+	p.fmt.uniQuote = false
+	p.fmt.prec = prec
+	p.fmt.precPresent = precPresent
+	p.fmt.sharp = sharp
+}
+
+func (p *pp) fmtUint64(v uint64, verb rune) {
+	switch verb {
+	case 'b':
+		p.fmt.integer(int64(v), 2, unsigned, ldigits)
+	case 'c':
+		p.fmtC(int64(v))
+	case 'd':
+		p.fmt.integer(int64(v), 10, unsigned, ldigits)
+	case 'v':
+		if p.fmt.sharpV {
+			p.fmt0x64(v, true)
+		} else {
+			p.fmt.integer(int64(v), 10, unsigned, ldigits)
+		}
+	case 'o':
+		p.fmt.integer(int64(v), 8, unsigned, ldigits)
+	case 'q':
+		if 0 <= v && v <= utf8.MaxRune {
+			p.fmt.fmt_qc(int64(v))
+		} else {
+			p.badVerb(verb)
+		}
+	case 'x':
+		p.fmt.integer(int64(v), 16, unsigned, ldigits)
+	case 'X':
+		p.fmt.integer(int64(v), 16, unsigned, udigits)
+	case 'U':
+		p.fmtUnicode(int64(v))
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) fmtFloat32(v float32, verb rune) {
+	switch verb {
+	case 'b':
+		p.fmt.fmt_fb32(v)
+	case 'e':
+		p.fmt.fmt_e32(v)
+	case 'E':
+		p.fmt.fmt_E32(v)
+	case 'f', 'F':
+		p.fmt.fmt_f32(v)
+	case 'g', 'v':
+		p.fmt.fmt_g32(v)
+	case 'G':
+		p.fmt.fmt_G32(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) fmtFloat64(v float64, verb rune) {
+	switch verb {
+	case 'b':
+		p.fmt.fmt_fb64(v)
+	case 'e':
+		p.fmt.fmt_e64(v)
+	case 'E':
+		p.fmt.fmt_E64(v)
+	case 'f', 'F':
+		p.fmt.fmt_f64(v)
+	case 'g', 'v':
+		p.fmt.fmt_g64(v)
+	case 'G':
+		p.fmt.fmt_G64(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) fmtComplex64(v complex64, verb rune) {
+	switch verb {
+	case 'b', 'e', 'E', 'f', 'F', 'g', 'G':
+		p.fmt.fmt_c64(v, verb)
+	case 'v':
+		p.fmt.fmt_c64(v, 'g')
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) fmtComplex128(v complex128, verb rune) {
+	switch verb {
+	case 'b', 'e', 'E', 'f', 'F', 'g', 'G':
+		p.fmt.fmt_c128(v, verb)
+	case 'v':
+		p.fmt.fmt_c128(v, 'g')
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) fmtString(v string, verb rune) {
+	switch verb {
+	case 'v':
+		if p.fmt.sharpV {
+			p.fmt.fmt_q(v)
+		} else {
+			p.fmt.fmt_s(v)
+		}
+	case 's':
+		p.fmt.fmt_s(v)
+	case 'x':
+		p.fmt.fmt_sx(v, ldigits)
+	case 'X':
+		p.fmt.fmt_sx(v, udigits)
+	case 'q':
+		p.fmt.fmt_q(v)
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) fmtBytes(v []byte, verb rune, typ reflect.Type, depth int) {
+	if verb == 'v' || verb == 'd' {
+		if p.fmt.sharpV {
+			if v == nil {
+				if typ == nil {
+					p.buf.WriteString("[]byte(nil)")
+				} else {
+					p.buf.WriteString(typ.String())
+					p.buf.Write(nilParenBytes)
+				}
+				return
+			}
+			if typ == nil {
+				p.buf.Write(bytesBytes)
+			} else {
+				p.buf.WriteString(typ.String())
+				p.buf.WriteByte('{')
+			}
+		} else {
+			p.buf.WriteByte('[')
+		}
+		for i, c := range v {
+			if i > 0 {
+				if p.fmt.sharpV {
+					p.buf.Write(commaSpaceBytes)
+				} else {
+					p.buf.WriteByte(' ')
+				}
+			}
+			p.printArg(c, 'v', depth+1)
+		}
+		if p.fmt.sharpV {
+			p.buf.WriteByte('}')
+		} else {
+			p.buf.WriteByte(']')
+		}
+		return
+	}
+	switch verb {
+	case 's':
+		p.fmt.fmt_s(string(v))
+	case 'x':
+		p.fmt.fmt_bx(v, ldigits)
+	case 'X':
+		p.fmt.fmt_bx(v, udigits)
+	case 'q':
+		p.fmt.fmt_q(string(v))
+	default:
+		p.badVerb(verb)
+	}
+}
+
+func (p *pp) fmtPointer(value reflect.Value, verb rune) {
+	use0x64 := true
+	switch verb {
+	case 'p', 'v':
+		// ok
+	case 'b', 'd', 'o', 'x', 'X':
+		use0x64 = false
+		// ok
+	default:
+		p.badVerb(verb)
+		return
+	}
+
+	var u uintptr
+	switch value.Kind() {
+	case reflect.Chan, reflect.Func, reflect.Map, reflect.Ptr, reflect.Slice, reflect.UnsafePointer:
+		u = value.Pointer()
+	default:
+		p.badVerb(verb)
+		return
+	}
+
+	if p.fmt.sharpV {
+		p.add('(')
+		p.buf.WriteString(value.Type().String())
+		p.add(')')
+		p.add('(')
+		if u == 0 {
+			p.buf.Write(nilBytes)
+		} else {
+			p.fmt0x64(uint64(u), true)
+		}
+		p.add(')')
+	} else if verb == 'v' && u == 0 {
+		p.buf.Write(nilAngleBytes)
+	} else {
+		if use0x64 {
+			p.fmt0x64(uint64(u), !p.fmt.sharp)
+		} else {
+			p.fmtUint64(uint64(u), verb)
+		}
+	}
+}
+
+var (
+	intBits     = reflect.TypeOf(0).Bits()
+	uintptrBits = reflect.TypeOf(uintptr(0)).Bits()
+)
+
+func (p *pp) catchPanic(arg interface{}, verb rune) {
+	if err := recover(); err != nil {
+		// If it's a nil pointer, just say "<nil>". The likeliest causes are a
+		// Stringer that fails to guard against nil or a nil pointer for a
+		// value receiver, and in either case, "<nil>" is a nice result.
+		if v := reflect.ValueOf(arg); v.Kind() == reflect.Ptr && v.IsNil() {
+			p.buf.Write(nilAngleBytes)
+			return
+		}
+		// Otherwise print a concise panic message. Most of the time the panic
+		// value will print itself nicely.
+		if p.panicking {
+			// Nested panics; the recursion in printArg cannot succeed.
+			panic(err)
+		}
+		p.fmt.clearflags() // We are done, and for this output we want default behavior.
+		p.buf.Write(percentBangBytes)
+		p.add(verb)
+		p.buf.Write(panicBytes)
+		p.panicking = true
+		p.printArg(err, 'v', 0)
+		p.panicking = false
+		p.buf.WriteByte(')')
+	}
+}
+
+// clearSpecialFlags pushes %#v back into the regular flags and returns their old state.
+func (p *pp) clearSpecialFlags() (plusV, sharpV bool) {
+	plusV = p.fmt.plusV
+	if plusV {
+		p.fmt.plus = true
+		p.fmt.plusV = false
+	}
+	sharpV = p.fmt.sharpV
+	if sharpV {
+		p.fmt.sharp = true
+		p.fmt.sharpV = false
+	}
+	return
+}
+
+// restoreSpecialFlags, whose argument should be a call to clearSpecialFlags,
+// restores the setting of the plusV and sharpV flags.
+func (p *pp) restoreSpecialFlags(plusV, sharpV bool) {
+	if plusV {
+		p.fmt.plus = false
+		p.fmt.plusV = true
+	}
+	if sharpV {
+		p.fmt.sharp = false
+		p.fmt.sharpV = true
+	}
+}
+
+func (p *pp) handleMethods(verb rune, depth int) (handled bool) {
+	if p.erroring {
+		return
+	}
+	// Is it a Formatter?
+	if formatter, ok := p.arg.(Formatter); ok {
+		handled = true
+		defer p.restoreSpecialFlags(p.clearSpecialFlags())
+		defer p.catchPanic(p.arg, verb)
+		formatter.Format(p, verb)
+		return
+	}
+
+	// If we're doing Go syntax and the argument knows how to supply it, take care of it now.
+	if p.fmt.sharpV {
+		if stringer, ok := p.arg.(GoStringer); ok {
+			handled = true
+			defer p.catchPanic(p.arg, verb)
+			// Print the result of GoString unadorned.
+			p.fmt.fmt_s(stringer.GoString())
+			return
+		}
+	} else {
+		// If a string is acceptable according to the format, see if
+		// the value satisfies one of the string-valued interfaces.
+		// Println etc. set verb to %v, which is "stringable".
+		switch verb {
+		case 'v', 's', 'x', 'X', 'q':
+			// Is it an error or Stringer?
+			// The duplication in the bodies is necessary:
+			// setting handled and deferring catchPanic
+			// must happen before calling the method.
+			switch v := p.arg.(type) {
+			case error:
+				handled = true
+				defer p.catchPanic(p.arg, verb)
+				p.printArg(v.Error(), verb, depth)
+				return
+
+			case Stringer:
+				handled = true
+				defer p.catchPanic(p.arg, verb)
+				p.printArg(v.String(), verb, depth)
+				return
+			}
+		}
+	}
+	return false
+}
+
+func (p *pp) printArg(arg interface{}, verb rune, depth int) (wasString bool) {
+	p.arg = arg
+	p.value = reflect.Value{}
+
+	if arg == nil {
+		if verb == 'T' || verb == 'v' {
+			p.fmt.pad(nilAngleBytes)
+		} else {
+			p.badVerb(verb)
+		}
+		return false
+	}
+
+	// Special processing considerations.
+	// %T (the value's type) and %p (its address) are special; we always do them first.
+	switch verb {
+	case 'T':
+		p.printArg(reflect.TypeOf(arg).String(), 's', 0)
+		return false
+	case 'p':
+		p.fmtPointer(reflect.ValueOf(arg), verb)
+		return false
+	}
+
+	// Some types can be done without reflection.
+	switch f := arg.(type) {
+	case bool:
+		p.fmtBool(f, verb)
+	case float32:
+		p.fmtFloat32(f, verb)
+	case float64:
+		p.fmtFloat64(f, verb)
+	case complex64:
+		p.fmtComplex64(f, verb)
+	case complex128:
+		p.fmtComplex128(f, verb)
+	case int:
+		p.fmtInt64(int64(f), verb)
+	case int8:
+		p.fmtInt64(int64(f), verb)
+	case int16:
+		p.fmtInt64(int64(f), verb)
+	case int32:
+		p.fmtInt64(int64(f), verb)
+	case int64:
+		p.fmtInt64(f, verb)
+	case uint:
+		p.fmtUint64(uint64(f), verb)
+	case uint8:
+		p.fmtUint64(uint64(f), verb)
+	case uint16:
+		p.fmtUint64(uint64(f), verb)
+	case uint32:
+		p.fmtUint64(uint64(f), verb)
+	case uint64:
+		p.fmtUint64(f, verb)
+	case uintptr:
+		p.fmtUint64(uint64(f), verb)
+	case string:
+		p.fmtString(f, verb)
+		wasString = verb == 's' || verb == 'v'
+	case []byte:
+		p.fmtBytes(f, verb, nil, depth)
+		wasString = verb == 's'
+	case reflect.Value:
+		return p.printReflectValue(f, verb, depth)
+	default:
+		// If the type is not simple, it might have methods.
+		if handled := p.handleMethods(verb, depth); handled {
+			return false
+		}
+		// Need to use reflection
+		return p.printReflectValue(reflect.ValueOf(arg), verb, depth)
+	}
+	p.arg = nil
+	return
+}
+
+// printValue is like printArg but starts with a reflect value, not an interface{} value.
+func (p *pp) printValue(value reflect.Value, verb rune, depth int) (wasString bool) {
+	if !value.IsValid() {
+		if verb == 'T' || verb == 'v' {
+			p.buf.Write(nilAngleBytes)
+		} else {
+			p.badVerb(verb)
+		}
+		return false
+	}
+
+	// Special processing considerations.
+	// %T (the value's type) and %p (its address) are special; we always do them first.
+	switch verb {
+	case 'T':
+		p.printArg(value.Type().String(), 's', 0)
+		return false
+	case 'p':
+		p.fmtPointer(value, verb)
+		return false
+	}
+
+	// Handle values with special methods.
+	// Call always, even when arg == nil, because handleMethods clears p.fmt.plus for us.
+	p.arg = nil // Make sure it's cleared, for safety.
+	if value.CanInterface() {
+		p.arg = value.Interface()
+	}
+	if handled := p.handleMethods(verb, depth); handled {
+		return false
+	}
+
+	return p.printReflectValue(value, verb, depth)
+}
+
+var byteType = reflect.TypeOf(byte(0))
+
+// printReflectValue is the fallback for both printArg and printValue.
+// It uses reflect to print the value.
+func (p *pp) printReflectValue(value reflect.Value, verb rune, depth int) (wasString bool) {
+	oldValue := p.value
+	p.value = value
+BigSwitch:
+	switch f := value; f.Kind() {
+	case reflect.Invalid:
+		p.buf.WriteString("<invalid reflect.Value>")
+	case reflect.Bool:
+		p.fmtBool(f.Bool(), verb)
+	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+		p.fmtInt64(f.Int(), verb)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+		p.fmtUint64(f.Uint(), verb)
+	case reflect.Float32, reflect.Float64:
+		if f.Type().Size() == 4 {
+			p.fmtFloat32(float32(f.Float()), verb)
+		} else {
+			p.fmtFloat64(f.Float(), verb)
+		}
+	case reflect.Complex64, reflect.Complex128:
+		if f.Type().Size() == 8 {
+			p.fmtComplex64(complex64(f.Complex()), verb)
+		} else {
+			p.fmtComplex128(f.Complex(), verb)
+		}
+	case reflect.String:
+		p.fmtString(f.String(), verb)
+	case reflect.Map:
+		if p.fmt.sharpV {
+			p.buf.WriteString(f.Type().String())
+			if f.IsNil() {
+				p.buf.WriteString("(nil)")
+				break
+			}
+			p.buf.WriteByte('{')
+		} else {
+			p.buf.Write(mapBytes)
+		}
+		keys := f.MapKeys()
+		for i, key := range keys {
+			if i > 0 {
+				if p.fmt.sharpV {
+					p.buf.Write(commaSpaceBytes)
+				} else {
+					p.buf.WriteByte(' ')
+				}
+			}
+			p.printValue(key, verb, depth+1)
+			p.buf.WriteByte(':')
+			p.printValue(f.MapIndex(key), verb, depth+1)
+		}
+		if p.fmt.sharpV {
+			p.buf.WriteByte('}')
+		} else {
+			p.buf.WriteByte(']')
+		}
+	case reflect.Struct:
+		if p.fmt.sharpV {
+			p.buf.WriteString(value.Type().String())
+		}
+		p.add('{')
+		v := f
+		t := v.Type()
+		for i := 0; i < v.NumField(); i++ {
+			if i > 0 {
+				if p.fmt.sharpV {
+					p.buf.Write(commaSpaceBytes)
+				} else {
+					p.buf.WriteByte(' ')
+				}
+			}
+			if p.fmt.plusV || p.fmt.sharpV {
+				if f := t.Field(i); f.Name != "" {
+					p.buf.WriteString(f.Name)
+					p.buf.WriteByte(':')
+				}
+			}
+			p.printValue(getField(v, i), verb, depth+1)
+		}
+		p.buf.WriteByte('}')
+	case reflect.Interface:
+		value := f.Elem()
+		if !value.IsValid() {
+			if p.fmt.sharpV {
+				p.buf.WriteString(f.Type().String())
+				p.buf.Write(nilParenBytes)
+			} else {
+				p.buf.Write(nilAngleBytes)
+			}
+		} else {
+			wasString = p.printValue(value, verb, depth+1)
+		}
+	case reflect.Array, reflect.Slice:
+		// Byte slices are special:
+		// - Handle []byte (== []uint8) with fmtBytes.
+		// - Handle []T, where T is a named byte type, with fmtBytes only
+		//   for the s, q, an x verbs. For other verbs, T might be a
+		//   Stringer, so we use printValue to print each element.
+		if typ := f.Type(); typ.Elem().Kind() == reflect.Uint8 && (typ.Elem() == byteType || verb == 's' || verb == 'q' || verb == 'x') {
+			var bytes []byte
+			if f.Kind() == reflect.Slice {
+				bytes = f.Bytes()
+			} else if f.CanAddr() {
+				bytes = f.Slice(0, f.Len()).Bytes()
+			} else {
+				// We have an array, but we cannot Slice() a non-addressable array,
+				// so we build a slice by hand. This is a rare case but it would be nice
+				// if reflection could help a little more.
+				bytes = make([]byte, f.Len())
+				for i := range bytes {
+					bytes[i] = byte(f.Index(i).Uint())
+				}
+			}
+			p.fmtBytes(bytes, verb, typ, depth)
+			wasString = verb == 's'
+			break
+		}
+		if p.fmt.sharpV {
+			p.buf.WriteString(value.Type().String())
+			if f.Kind() == reflect.Slice && f.IsNil() {
+				p.buf.WriteString("(nil)")
+				break
+			}
+			p.buf.WriteByte('{')
+		} else {
+			p.buf.WriteByte('[')
+		}
+		for i := 0; i < f.Len(); i++ {
+			if i > 0 {
+				if p.fmt.sharpV {
+					p.buf.Write(commaSpaceBytes)
+				} else {
+					p.buf.WriteByte(' ')
+				}
+			}
+			p.printValue(f.Index(i), verb, depth+1)
+		}
+		if p.fmt.sharpV {
+			p.buf.WriteByte('}')
+		} else {
+			p.buf.WriteByte(']')
+		}
+	case reflect.Ptr:
+		v := f.Pointer()
+		// pointer to array or slice or struct?  ok at top level
+		// but not embedded (avoid loops)
+		if v != 0 && depth == 100 {
+			switch a := f.Elem(); a.Kind() {
+			case reflect.Array, reflect.Slice:
+				p.buf.WriteByte('&')
+				p.printValue(a, verb, depth+1)
+				break BigSwitch
+			case reflect.Struct:
+				p.buf.WriteByte('&')
+				p.printValue(a, verb, depth+1)
+				break BigSwitch
+			case reflect.Map:
+				p.buf.WriteByte('&')
+				p.printValue(a, verb, depth+1)
+				break BigSwitch
+			}
+		}
+		fallthrough
+	case reflect.Chan, reflect.Func, reflect.UnsafePointer:
+		p.fmtPointer(value, verb)
+	default:
+		p.unknownType(f)
+	}
+	p.value = oldValue
+	return wasString
+}
+
+// intFromArg gets the argNumth element of a. On return, isInt reports whether the argument has type int.
+func intFromArg(a []interface{}, argNum int) (num int, isInt bool, newArgNum int) {
+	newArgNum = argNum
+	if argNum < len(a) {
+		num, isInt = a[argNum].(int)
+		newArgNum = argNum + 1
+		if tooLarge(num) {
+			num = 0
+			isInt = false
+		}
+	}
+	return
+}
+
+// parseArgNumber returns the value of the bracketed number, minus 1
+// (explicit argument numbers are one-indexed but we want zero-indexed).
+// The opening bracket is known to be present at format[0].
+// The returned values are the index, the number of bytes to consume
+// up to the closing paren, if present, and whether the number parsed
+// ok. The bytes to consume will be 1 if no closing paren is present.
+func parseArgNumber(format string) (index int, wid int, ok bool) {
+	// There must be at least 3 bytes: [n].
+	if len(format) < 3 {
+		return 0, 1, false
+	}
+
+	// Find closing bracket.
+	for i := 1; i < len(format); i++ {
+		if format[i] == ']' {
+			width, ok, newi := parsenum(format, 1, i)
+			if !ok || newi != i {
+				return 0, i + 1, false
+			}
+			return width - 1, i + 1, true // arg numbers are one-indexed and skip paren.
+		}
+	}
+	return 0, 1, false
+}
+
+// argNumber returns the next argument to evaluate, which is either the value of the passed-in
+// argNum or the value of the bracketed integer that begins format[i:]. It also returns
+// the new value of i, that is, the index of the next byte of the format to process.
+func (p *pp) argNumber(argNum int, format string, i int, numArgs int) (newArgNum, newi int, found bool) {
+	if len(format) <= i || format[i] != '[' {
+		return argNum, i, false
+	}
+	p.reordered = true
+	index, wid, ok := parseArgNumber(format[i:])
+	if ok && 0 <= index && index < numArgs {
+		return index, i + wid, true
+	}
+	p.goodArgNum = false
+	return argNum, i + wid, ok
+}
+
+func (p *pp) doPrintf(format string, a []interface{}) {
+	end := len(format)
+	argNum := 0         // we process one argument per non-trivial format
+	afterIndex := false // previous item in format was an index like [3].
+	p.reordered = false
+	for i := 0; i < end; {
+		p.goodArgNum = true
+		lasti := i
+		for i < end && format[i] != '%' {
+			i++
+		}
+		if i > lasti {
+			p.buf.WriteString(format[lasti:i])
+		}
+		if i >= end {
+			// done processing format string
+			break
+		}
+
+		// Process one verb
+		i++
+
+		// Do we have flags?
+		p.fmt.clearflags()
+	F:
+		for ; i < end; i++ {
+			switch format[i] {
+			case '#':
+				p.fmt.sharp = true
+			case '0':
+				p.fmt.zero = true
+			case '+':
+				p.fmt.plus = true
+			case '-':
+				p.fmt.minus = true
+			case ' ':
+				p.fmt.space = true
+			default:
+				break F
+			}
+		}
+
+		// Do we have an explicit argument index?
+		argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
+
+		// Do we have width?
+		if i < end && format[i] == '*' {
+			i++
+			p.fmt.wid, p.fmt.widPresent, argNum = intFromArg(a, argNum)
+
+			if !p.fmt.widPresent {
+				p.buf.Write(badWidthBytes)
+			}
+
+			// We have a negative width, so take its value and ensure
+			// that the minus flag is set
+			if p.fmt.wid < 0 {
+				p.fmt.wid = -p.fmt.wid
+				p.fmt.minus = true
+			}
+			afterIndex = false
+		} else {
+			p.fmt.wid, p.fmt.widPresent, i = parsenum(format, i, end)
+			if afterIndex && p.fmt.widPresent { // "%[3]2d"
+				p.goodArgNum = false
+			}
+		}
+
+		// Do we have precision?
+		if i+1 < end && format[i] == '.' {
+			i++
+			if afterIndex { // "%[3].2d"
+				p.goodArgNum = false
+			}
+			argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
+			if i < end && format[i] == '*' {
+				i++
+				p.fmt.prec, p.fmt.precPresent, argNum = intFromArg(a, argNum)
+				// Negative precision arguments don't make sense
+				if p.fmt.prec < 0 {
+					p.fmt.prec = 0
+					p.fmt.precPresent = false
+				}
+				if !p.fmt.precPresent {
+					p.buf.Write(badPrecBytes)
+				}
+				afterIndex = false
+			} else {
+				p.fmt.prec, p.fmt.precPresent, i = parsenum(format, i, end)
+				if !p.fmt.precPresent {
+					p.fmt.prec = 0
+					p.fmt.precPresent = true
+				}
+			}
+		}
+
+		if !afterIndex {
+			argNum, i, afterIndex = p.argNumber(argNum, format, i, len(a))
+		}
+
+		if i >= end {
+			p.buf.Write(noVerbBytes)
+			continue
+		}
+		c, w := utf8.DecodeRuneInString(format[i:])
+		i += w
+		// percent is special - absorbs no operand
+		if c == '%' {
+			p.buf.WriteByte('%') // We ignore width and prec.
+			continue
+		}
+		if !p.goodArgNum {
+			p.buf.Write(percentBangBytes)
+			p.add(c)
+			p.buf.Write(badIndexBytes)
+			continue
+		} else if argNum >= len(a) { // out of operands
+			p.buf.Write(percentBangBytes)
+			p.add(c)
+			p.buf.Write(missingBytes)
+			continue
+		}
+		arg := a[argNum]
+		argNum++
+
+		if c == 'v' {
+			if p.fmt.sharp {
+				// Go syntax. Set the flag in the fmt and clear the sharp flag.
+				p.fmt.sharp = false
+				p.fmt.sharpV = true
+			}
+			if p.fmt.plus {
+				// Struct-field syntax. Set the flag in the fmt and clear the plus flag.
+				p.fmt.plus = false
+				p.fmt.plusV = true
+			}
+		}
+		p.printArg(arg, c, 0)
+	}
+
+	// Check for extra arguments unless the call accessed the arguments
+	// out of order, in which case it's too expensive to detect if they've all
+	// been used and arguably OK if they're not.
+	if !p.reordered && argNum < len(a) {
+		p.buf.Write(extraBytes)
+		for ; argNum < len(a); argNum++ {
+			arg := a[argNum]
+			if arg != nil {
+				p.buf.WriteString(reflect.TypeOf(arg).String())
+				p.buf.WriteByte('=')
+			}
+			p.printArg(arg, 'v', 0)
+			if argNum+1 < len(a) {
+				p.buf.Write(commaSpaceBytes)
+			}
+		}
+		p.buf.WriteByte(')')
+	}
+}
+
+func (p *pp) doPrint(a []interface{}, addspace, addnewline bool) {
+	prevString := false
+	for argNum := 0; argNum < len(a); argNum++ {
+		p.fmt.clearflags()
+		// always add spaces if we're doing Println
+		arg := a[argNum]
+		if argNum > 0 {
+			isString := arg != nil && reflect.TypeOf(arg).Kind() == reflect.String
+			if addspace || !isString && !prevString {
+				p.buf.WriteByte(' ')
+			}
+		}
+		prevString = p.printArg(arg, 'v', 0)
+	}
+	if addnewline {
+		p.buf.WriteByte('\n')
+	}
+}