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|
package time
import "errors"
const (
numeric = iota
alphabetic
separator
plus
minus
)
// These are predefined layouts for use in Time.Format.
// The standard time used in the layouts is:
// Mon Jan 2 15:04:05 MST 2006 (MST is GMT-0700)
// which is Unix time 1136243045.
// (Think of it as 01/02 03:04:05PM '06 -0700.)
// To define your own format, write down what the standard
// time would look like formatted your way.
//
// Within the format string, an underscore _ represents a space that may be
// replaced by a digit if the following number (a day) has two digits; for
// compatibility with fixed-width Unix time formats.
//
// A decimal point followed by one or more zeros represents a fractional
// second. When parsing (only), the input may contain a fractional second
// field immediately after the seconds field, even if the layout does not
// signify its presence. In that case a decimal point followed by a maximal
// series of digits is parsed as a fractional second.
//
// Numeric time zone offsets format as follows:
// -0700 ±hhmm
// -07:00 ±hh:mm
// Replacing the sign in the format with a Z triggers
// the ISO 8601 behavior of printing Z instead of an
// offset for the UTC zone. Thus:
// Z0700 Z or ±hhmm
// Z07:00 Z or ±hh:mm
const (
ANSIC = "Mon Jan _2 15:04:05 2006"
UnixDate = "Mon Jan _2 15:04:05 MST 2006"
RubyDate = "Mon Jan 02 15:04:05 -0700 2006"
RFC822 = "02 Jan 06 1504 MST"
RFC822Z = "02 Jan 06 1504 -0700" // RFC822 with numeric zone
RFC850 = "Monday, 02-Jan-06 15:04:05 MST"
RFC1123 = "Mon, 02 Jan 2006 15:04:05 MST"
RFC1123Z = "Mon, 02 Jan 2006 15:04:05 -0700" // RFC1123 with numeric zone
RFC3339 = "2006-01-02T15:04:05Z07:00"
Kitchen = "3:04PM"
// Handy time stamps.
Stamp = "Jan _2 15:04:05"
StampMilli = "Jan _2 15:04:05.000"
StampMicro = "Jan _2 15:04:05.000000"
StampNano = "Jan _2 15:04:05.000000000"
)
const (
stdLongMonth = "January"
stdMonth = "Jan"
stdNumMonth = "1"
stdZeroMonth = "01"
stdLongWeekDay = "Monday"
stdWeekDay = "Mon"
stdDay = "2"
stdUnderDay = "_2"
stdZeroDay = "02"
stdHour = "15"
stdHour12 = "3"
stdZeroHour12 = "03"
stdMinute = "4"
stdZeroMinute = "04"
stdSecond = "5"
stdZeroSecond = "05"
stdLongYear = "2006"
stdYear = "06"
stdPM = "PM"
stdpm = "pm"
stdTZ = "MST"
stdISO8601TZ = "Z0700" // prints Z for UTC
stdISO8601ColonTZ = "Z07:00" // prints Z for UTC
stdNumTZ = "-0700" // always numeric
stdNumShortTZ = "-07" // always numeric
stdNumColonTZ = "-07:00" // always numeric
)
// nextStdChunk finds the first occurrence of a std string in
// layout and returns the text before, the std string, and the text after.
func nextStdChunk(layout string) (prefix, std, suffix string) {
for i := 0; i < len(layout); i++ {
switch layout[i] {
case 'J': // January, Jan
if len(layout) >= i+7 && layout[i:i+7] == stdLongMonth {
return layout[0:i], stdLongMonth, layout[i+7:]
}
if len(layout) >= i+3 && layout[i:i+3] == stdMonth {
return layout[0:i], stdMonth, layout[i+3:]
}
case 'M': // Monday, Mon, MST
if len(layout) >= i+6 && layout[i:i+6] == stdLongWeekDay {
return layout[0:i], stdLongWeekDay, layout[i+6:]
}
if len(layout) >= i+3 {
if layout[i:i+3] == stdWeekDay {
return layout[0:i], stdWeekDay, layout[i+3:]
}
if layout[i:i+3] == stdTZ {
return layout[0:i], stdTZ, layout[i+3:]
}
}
case '0': // 01, 02, 03, 04, 05, 06
if len(layout) >= i+2 && '1' <= layout[i+1] && layout[i+1] <= '6' {
return layout[0:i], layout[i : i+2], layout[i+2:]
}
case '1': // 15, 1
if len(layout) >= i+2 && layout[i+1] == '5' {
return layout[0:i], stdHour, layout[i+2:]
}
return layout[0:i], stdNumMonth, layout[i+1:]
case '2': // 2006, 2
if len(layout) >= i+4 && layout[i:i+4] == stdLongYear {
return layout[0:i], stdLongYear, layout[i+4:]
}
return layout[0:i], stdDay, layout[i+1:]
case '_': // _2
if len(layout) >= i+2 && layout[i+1] == '2' {
return layout[0:i], stdUnderDay, layout[i+2:]
}
case '3', '4', '5': // 3, 4, 5
return layout[0:i], layout[i : i+1], layout[i+1:]
case 'P': // PM
if len(layout) >= i+2 && layout[i+1] == 'M' {
return layout[0:i], layout[i : i+2], layout[i+2:]
}
case 'p': // pm
if len(layout) >= i+2 && layout[i+1] == 'm' {
return layout[0:i], layout[i : i+2], layout[i+2:]
}
case '-': // -0700, -07:00, -07
if len(layout) >= i+5 && layout[i:i+5] == stdNumTZ {
return layout[0:i], layout[i : i+5], layout[i+5:]
}
if len(layout) >= i+6 && layout[i:i+6] == stdNumColonTZ {
return layout[0:i], layout[i : i+6], layout[i+6:]
}
if len(layout) >= i+3 && layout[i:i+3] == stdNumShortTZ {
return layout[0:i], layout[i : i+3], layout[i+3:]
}
case 'Z': // Z0700, Z07:00
if len(layout) >= i+5 && layout[i:i+5] == stdISO8601TZ {
return layout[0:i], layout[i : i+5], layout[i+5:]
}
if len(layout) >= i+6 && layout[i:i+6] == stdISO8601ColonTZ {
return layout[0:i], layout[i : i+6], layout[i+6:]
}
case '.': // .000 - multiple digits of zeros (only) for fractional seconds.
numZeros := 0
var j int
for j = i + 1; j < len(layout) && layout[j] == '0'; j++ {
numZeros++
}
// String of digits must end here - only fractional second is all zeros.
if numZeros > 0 && !isDigit(layout, j) {
return layout[0:i], layout[i : i+1+numZeros], layout[i+1+numZeros:]
}
}
}
return layout, "", ""
}
var longDayNames = []string{
"Sunday",
"Monday",
"Tuesday",
"Wednesday",
"Thursday",
"Friday",
"Saturday",
}
var shortDayNames = []string{
"Sun",
"Mon",
"Tue",
"Wed",
"Thu",
"Fri",
"Sat",
}
var shortMonthNames = []string{
"---",
"Jan",
"Feb",
"Mar",
"Apr",
"May",
"Jun",
"Jul",
"Aug",
"Sep",
"Oct",
"Nov",
"Dec",
}
var longMonthNames = []string{
"---",
"January",
"February",
"March",
"April",
"May",
"June",
"July",
"August",
"September",
"October",
"November",
"December",
}
// match returns true if s1 and s2 match ignoring case.
// It is assumed s1 and s2 are the same length.
func match(s1, s2 string) bool {
for i := 0; i < len(s1); i++ {
c1 := s1[i]
c2 := s2[i]
if c1 != c2 {
// Switch to lower-case; 'a'-'A' is known to be a single bit.
c1 |= 'a' - 'A'
c2 |= 'a' - 'A'
if c1 != c2 || c1 < 'a' || c1 > 'z' {
return false
}
}
}
return true
}
func lookup(tab []string, val string) (int, string, error) {
for i, v := range tab {
if len(val) >= len(v) && match(val[0:len(v)], v) {
return i, val[len(v):], nil
}
}
return -1, val, errBad
}
// Duplicates functionality in strconv, but avoids dependency.
func itoa(x int) string {
var buf [32]byte
n := len(buf)
if x == 0 {
return "0"
}
u := uint(x)
if x < 0 {
u = -u
}
for u > 0 {
n--
buf[n] = byte(u%10 + '0')
u /= 10
}
if x < 0 {
n--
buf[n] = '-'
}
return string(buf[n:])
}
// Never printed, just needs to be non-nil for return by atoi.
var atoiError = errors.New("time: invalid number")
// Duplicates functionality in strconv, but avoids dependency.
func atoi(s string) (x int, err error) {
neg := false
if s != "" && s[0] == '-' {
neg = true
s = s[1:]
}
x, rem, err := leadingInt(s)
if err != nil || rem != "" {
return 0, atoiError
}
if neg {
x = -x
}
return x, nil
}
func pad(i int, padding string) string {
s := itoa(i)
if i < 10 {
s = padding + s
}
return s
}
func zeroPad(i int) string { return pad(i, "0") }
// formatNano formats a fractional second, as nanoseconds.
func formatNano(nanosec, n int) string {
// User might give us bad data. Make sure it's positive and in range.
// They'll get nonsense output but it will have the right format.
s := itoa(int(uint(nanosec) % 1e9))
// Zero pad left without fmt.
if len(s) < 9 {
s = "000000000"[:9-len(s)] + s
}
if n > 9 {
n = 9
}
return "." + s[:n]
}
// String returns the time formatted using the format string
// "Mon Jan _2 15:04:05 -0700 MST 2006"
func (t Time) String() string {
return t.Format("Mon Jan _2 15:04:05 -0700 MST 2006")
}
type buffer []byte
func (b *buffer) WriteString(s string) {
*b = append(*b, s...)
}
func (b *buffer) String() string {
return string([]byte(*b))
}
// Format returns a textual representation of the time value formatted
// according to layout. The layout defines the format by showing the
// representation of a standard time, which is then used to describe
// the time to be formatted. Predefined layouts ANSIC, UnixDate,
// RFC3339 and others describe standard representations. For more
// information about the formats, see the documentation for ANSIC.
func (t Time) Format(layout string) string {
var (
year int = -1
month Month
day int
hour int = -1
min int
sec int
b buffer
)
// Each iteration generates one std value.
for {
prefix, std, suffix := nextStdChunk(layout)
b.WriteString(prefix)
if std == "" {
break
}
// Compute year, month, day if needed.
if year < 0 {
// Jan 01 02 2006
if a, z := std[0], std[len(std)-1]; a == 'J' || a == 'j' || z == '1' || z == '2' || z == '6' {
year, month, day = t.Date()
}
}
// Compute hour, minute, second if needed.
if hour < 0 {
// 03 04 05 15 pm
if z := std[len(std)-1]; z == '3' || z == '4' || z == '5' || z == 'm' || z == 'M' {
hour, min, sec = t.Clock()
}
}
var p string
switch std {
case stdYear:
p = zeroPad(year % 100)
case stdLongYear:
p = itoa(year)
case stdMonth:
p = month.String()[:3]
case stdLongMonth:
p = month.String()
case stdNumMonth:
p = itoa(int(month))
case stdZeroMonth:
p = zeroPad(int(month))
case stdWeekDay:
p = t.Weekday().String()[:3]
case stdLongWeekDay:
p = t.Weekday().String()
case stdDay:
p = itoa(day)
case stdUnderDay:
p = pad(day, " ")
case stdZeroDay:
p = zeroPad(day)
case stdHour:
p = zeroPad(hour)
case stdHour12:
// Noon is 12PM, midnight is 12AM.
hr := hour % 12
if hr == 0 {
hr = 12
}
p = itoa(hr)
case stdZeroHour12:
// Noon is 12PM, midnight is 12AM.
hr := hour % 12
if hr == 0 {
hr = 12
}
p = zeroPad(hr)
case stdMinute:
p = itoa(min)
case stdZeroMinute:
p = zeroPad(min)
case stdSecond:
p = itoa(sec)
case stdZeroSecond:
p = zeroPad(sec)
case stdPM:
if hour >= 12 {
p = "PM"
} else {
p = "AM"
}
case stdpm:
if hour >= 12 {
p = "pm"
} else {
p = "am"
}
case stdISO8601TZ, stdISO8601ColonTZ, stdNumTZ, stdNumColonTZ:
// Ugly special case. We cheat and take the "Z" variants
// to mean "the time zone as formatted for ISO 8601".
_, offset := t.Zone()
if offset == 0 && std[0] == 'Z' {
p = "Z"
break
}
zone := offset / 60 // convert to minutes
if zone < 0 {
p = "-"
zone = -zone
} else {
p = "+"
}
p += zeroPad(zone / 60)
if std == stdISO8601ColonTZ || std == stdNumColonTZ {
p += ":"
}
p += zeroPad(zone % 60)
case stdTZ:
name, offset := t.Zone()
if name != "" {
p = name
} else {
// No time zone known for this time, but we must print one.
// Use the -0700 format.
zone := offset / 60 // convert to minutes
if zone < 0 {
p = "-"
zone = -zone
} else {
p = "+"
}
p += zeroPad(zone / 60)
p += zeroPad(zone % 60)
}
default:
if len(std) >= 2 && std[0:2] == ".0" {
p = formatNano(t.Nanosecond(), len(std)-1)
}
}
b.WriteString(p)
layout = suffix
}
return b.String()
}
var errBad = errors.New("bad value for field") // placeholder not passed to user
// ParseError describes a problem parsing a time string.
type ParseError struct {
Layout string
Value string
LayoutElem string
ValueElem string
Message string
}
func quote(s string) string {
return "\"" + s + "\""
}
// Error returns the string representation of a ParseError.
func (e *ParseError) Error() string {
if e.Message == "" {
return "parsing time " +
quote(e.Value) + " as " +
quote(e.Layout) + ": cannot parse " +
quote(e.ValueElem) + " as " +
quote(e.LayoutElem)
}
return "parsing time " +
quote(e.Value) + e.Message
}
// isDigit returns true if s[i] is a decimal digit, false if not or
// if s[i] is out of range.
func isDigit(s string, i int) bool {
if len(s) <= i {
return false
}
c := s[i]
return '0' <= c && c <= '9'
}
// getnum parses s[0:1] or s[0:2] (fixed forces the latter)
// as a decimal integer and returns the integer and the
// remainder of the string.
func getnum(s string, fixed bool) (int, string, error) {
if !isDigit(s, 0) {
return 0, s, errBad
}
if !isDigit(s, 1) {
if fixed {
return 0, s, errBad
}
return int(s[0] - '0'), s[1:], nil
}
return int(s[0]-'0')*10 + int(s[1]-'0'), s[2:], nil
}
func cutspace(s string) string {
for len(s) > 0 && s[0] == ' ' {
s = s[1:]
}
return s
}
// skip removes the given prefix from value,
// treating runs of space characters as equivalent.
func skip(value, prefix string) (string, error) {
for len(prefix) > 0 {
if prefix[0] == ' ' {
if len(value) > 0 && value[0] != ' ' {
return "", errBad
}
prefix = cutspace(prefix)
value = cutspace(value)
continue
}
if len(value) == 0 || value[0] != prefix[0] {
return "", errBad
}
prefix = prefix[1:]
value = value[1:]
}
return value, nil
}
// Parse parses a formatted string and returns the time value it represents.
// The layout defines the format by showing the representation of a standard
// time, which is then used to describe the string to be parsed. Predefined
// layouts ANSIC, UnixDate, RFC3339 and others describe standard
// representations.For more information about the formats, see the
// documentation for ANSIC.
//
// Elements omitted from the value are assumed to be zero, or when
// zero is impossible, one, so parsing "3:04pm" returns the time
// corresponding to Jan 1, year 0, 15:04:00 UTC.
// Years must be in the range 0000..9999. The day of the week is checked
// for syntax but it is otherwise ignored.
func Parse(layout, value string) (Time, error) {
alayout, avalue := layout, value
rangeErrString := "" // set if a value is out of range
amSet := false // do we need to subtract 12 from the hour for midnight?
pmSet := false // do we need to add 12 to the hour?
// Time being constructed.
var (
year int
month int = 1 // January
day int = 1
hour int
min int
sec int
nsec int
z *Location
zoneOffset int = -1
zoneName string
)
// Each iteration processes one std value.
for {
var err error
prefix, std, suffix := nextStdChunk(layout)
value, err = skip(value, prefix)
if err != nil {
return Time{}, &ParseError{alayout, avalue, prefix, value, ""}
}
if len(std) == 0 {
if len(value) != 0 {
return Time{}, &ParseError{alayout, avalue, "", value, ": extra text: " + value}
}
break
}
layout = suffix
var p string
switch std {
case stdYear:
if len(value) < 2 {
err = errBad
break
}
p, value = value[0:2], value[2:]
year, err = atoi(p)
if year >= 69 { // Unix time starts Dec 31 1969 in some time zones
year += 1900
} else {
year += 2000
}
case stdLongYear:
if len(value) < 4 || !isDigit(value, 0) {
err = errBad
break
}
p, value = value[0:4], value[4:]
year, err = atoi(p)
case stdMonth:
month, value, err = lookup(shortMonthNames, value)
case stdLongMonth:
month, value, err = lookup(longMonthNames, value)
case stdNumMonth, stdZeroMonth:
month, value, err = getnum(value, std == stdZeroMonth)
if month <= 0 || 12 < month {
rangeErrString = "month"
}
case stdWeekDay:
// Ignore weekday except for error checking.
_, value, err = lookup(shortDayNames, value)
case stdLongWeekDay:
_, value, err = lookup(longDayNames, value)
case stdDay, stdUnderDay, stdZeroDay:
if std == stdUnderDay && len(value) > 0 && value[0] == ' ' {
value = value[1:]
}
day, value, err = getnum(value, std == stdZeroDay)
if day < 0 || 31 < day {
rangeErrString = "day"
}
case stdHour:
hour, value, err = getnum(value, false)
if hour < 0 || 24 <= hour {
rangeErrString = "hour"
}
case stdHour12, stdZeroHour12:
hour, value, err = getnum(value, std == stdZeroHour12)
if hour < 0 || 12 < hour {
rangeErrString = "hour"
}
case stdMinute, stdZeroMinute:
min, value, err = getnum(value, std == stdZeroMinute)
if min < 0 || 60 <= min {
rangeErrString = "minute"
}
case stdSecond, stdZeroSecond:
sec, value, err = getnum(value, std == stdZeroSecond)
if sec < 0 || 60 <= sec {
rangeErrString = "second"
}
// Special case: do we have a fractional second but no
// fractional second in the format?
if len(value) > 2 && value[0] == '.' && isDigit(value, 1) {
_, std, _ := nextStdChunk(layout)
if len(std) > 0 && std[0] == '.' && isDigit(std, 1) {
// Fractional second in the layout; proceed normally
break
}
// No fractional second in the layout but we have one in the input.
n := 2
for ; n < len(value) && isDigit(value, n); n++ {
}
nsec, rangeErrString, err = parseNanoseconds(value, n)
value = value[n:]
}
case stdPM:
if len(value) < 2 {
err = errBad
break
}
p, value = value[0:2], value[2:]
switch p {
case "PM":
pmSet = true
case "AM":
amSet = true
default:
err = errBad
}
case stdpm:
if len(value) < 2 {
err = errBad
break
}
p, value = value[0:2], value[2:]
switch p {
case "pm":
pmSet = true
case "am":
amSet = true
default:
err = errBad
}
case stdISO8601TZ, stdISO8601ColonTZ, stdNumTZ, stdNumShortTZ, stdNumColonTZ:
if std[0] == 'Z' && len(value) >= 1 && value[0] == 'Z' {
value = value[1:]
z = UTC
break
}
var sign, hour, min string
if std == stdISO8601ColonTZ || std == stdNumColonTZ {
if len(value) < 6 {
err = errBad
break
}
if value[3] != ':' {
err = errBad
break
}
sign, hour, min, value = value[0:1], value[1:3], value[4:6], value[6:]
} else if std == stdNumShortTZ {
if len(value) < 3 {
err = errBad
break
}
sign, hour, min, value = value[0:1], value[1:3], "00", value[3:]
} else {
if len(value) < 5 {
err = errBad
break
}
sign, hour, min, value = value[0:1], value[1:3], value[3:5], value[5:]
}
var hr, mm int
hr, err = atoi(hour)
if err == nil {
mm, err = atoi(min)
}
zoneOffset = (hr*60 + mm) * 60 // offset is in seconds
switch sign[0] {
case '+':
case '-':
zoneOffset = -zoneOffset
default:
err = errBad
}
case stdTZ:
// Does it look like a time zone?
if len(value) >= 3 && value[0:3] == "UTC" {
z = UTC
value = value[3:]
break
}
if len(value) >= 3 && value[2] == 'T' {
p, value = value[0:3], value[3:]
} else if len(value) >= 4 && value[3] == 'T' {
p, value = value[0:4], value[4:]
} else {
err = errBad
break
}
for i := 0; i < len(p); i++ {
if p[i] < 'A' || 'Z' < p[i] {
err = errBad
}
}
if err != nil {
break
}
// It's a valid format.
zoneName = p
default:
if len(value) < len(std) {
err = errBad
break
}
if len(std) >= 2 && std[0:2] == ".0" {
nsec, rangeErrString, err = parseNanoseconds(value, len(std))
value = value[len(std):]
}
}
if rangeErrString != "" {
return Time{}, &ParseError{alayout, avalue, std, value, ": " + rangeErrString + " out of range"}
}
if err != nil {
return Time{}, &ParseError{alayout, avalue, std, value, ""}
}
}
if pmSet && hour < 12 {
hour += 12
} else if amSet && hour == 12 {
hour = 0
}
// TODO: be more aggressive checking day?
if z != nil {
return Date(year, Month(month), day, hour, min, sec, nsec, z), nil
}
t := Date(year, Month(month), day, hour, min, sec, nsec, UTC)
if zoneOffset != -1 {
t.sec -= int64(zoneOffset)
// Look for local zone with the given offset.
// If that zone was in effect at the given time, use it.
name, offset, _, _, _ := Local.lookup(t.sec + internalToUnix)
if offset == zoneOffset && (zoneName == "" || name == zoneName) {
t.loc = Local
return t, nil
}
// Otherwise create fake zone to record offset.
t.loc = FixedZone(zoneName, zoneOffset)
return t, nil
}
if zoneName != "" {
// Look for local zone with the given offset.
// If that zone was in effect at the given time, use it.
offset, _, ok := Local.lookupName(zoneName)
if ok {
name, off, _, _, _ := Local.lookup(t.sec + internalToUnix - int64(offset))
if name == zoneName && off == offset {
t.sec -= int64(offset)
t.loc = Local
return t, nil
}
}
// Otherwise, create fake zone with unknown offset.
t.loc = FixedZone(zoneName, 0)
return t, nil
}
// Otherwise, fall back to UTC.
return t, nil
}
func parseNanoseconds(value string, nbytes int) (ns int, rangeErrString string, err error) {
if value[0] != '.' {
err = errBad
return
}
ns, err = atoi(value[1:nbytes])
if err != nil {
return
}
if ns < 0 || 1e9 <= ns {
rangeErrString = "fractional second"
return
}
// We need nanoseconds, which means scaling by the number
// of missing digits in the format, maximum length 10. If it's
// longer than 10, we won't scale.
scaleDigits := 10 - nbytes
for i := 0; i < scaleDigits; i++ {
ns *= 10
}
return
}
var errLeadingInt = errors.New("time: bad [0-9]*") // never printed
// leadingInt consumes the leading [0-9]* from s.
func leadingInt(s string) (x int, rem string, err error) {
i := 0
for ; i < len(s); i++ {
c := s[i]
if c < '0' || c > '9' {
break
}
if x >= (1<<31-10)/10 {
// overflow
return 0, "", errLeadingInt
}
x = x*10 + int(c) - '0'
}
return x, s[i:], nil
}
var unitMap = map[string]float64{
"ns": float64(Nanosecond),
"us": float64(Microsecond),
"µs": float64(Microsecond), // U+00B5 = micro symbol
"μs": float64(Microsecond), // U+03BC = Greek letter mu
"ms": float64(Millisecond),
"s": float64(Second),
"m": float64(Minute),
"h": float64(Hour),
}
// ParseDuration parses a duration string.
// A duration string is a possibly signed sequence of
// decimal numbers, each with optional fraction and a unit suffix,
// such as "300ms", "-1.5h" or "2h45m".
// Valid time units are "ns", "us" (or "µs"), "ms", "s", "m", "h".
func ParseDuration(s string) (Duration, error) {
// [-+]?([0-9]*(\.[0-9]*)?[a-z]+)+
orig := s
f := float64(0)
neg := false
// Consume [-+]?
if s != "" {
c := s[0]
if c == '-' || c == '+' {
neg = c == '-'
s = s[1:]
}
}
// Special case: if all that is left is "0", this is zero.
if s == "0" {
return 0, nil
}
if s == "" {
return 0, errors.New("time: invalid duration " + orig)
}
for s != "" {
g := float64(0) // this element of the sequence
var x int
var err error
// The next character must be [0-9.]
if !(s[0] == '.' || ('0' <= s[0] && s[0] <= '9')) {
return 0, errors.New("time: invalid duration " + orig)
}
// Consume [0-9]*
pl := len(s)
x, s, err = leadingInt(s)
if err != nil {
return 0, errors.New("time: invalid duration " + orig)
}
g = float64(x)
pre := pl != len(s) // whether we consumed anything before a period
// Consume (\.[0-9]*)?
post := false
if s != "" && s[0] == '.' {
s = s[1:]
pl := len(s)
x, s, err = leadingInt(s)
if err != nil {
return 0, errors.New("time: invalid duration " + orig)
}
scale := 1
for n := pl - len(s); n > 0; n-- {
scale *= 10
}
g += float64(x) / float64(scale)
post = pl != len(s)
}
if !pre && !post {
// no digits (e.g. ".s" or "-.s")
return 0, errors.New("time: invalid duration " + orig)
}
// Consume unit.
i := 0
for ; i < len(s); i++ {
c := s[i]
if c == '.' || ('0' <= c && c <= '9') {
break
}
}
if i == 0 {
return 0, errors.New("time: missing unit in duration " + orig)
}
u := s[:i]
s = s[i:]
unit, ok := unitMap[u]
if !ok {
return 0, errors.New("time: unknown unit " + u + " in duration " + orig)
}
f += g * unit
}
if neg {
f = -f
}
return Duration(f), nil
}
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