1117 lines
30 KiB
Go
1117 lines
30 KiB
Go
// Copyright 2010 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package time
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import "errors"
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// These are predefined layouts for use in Time.Format and Time.Parse.
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// The reference time used in the layouts is:
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// Mon Jan 2 15:04:05 MST 2006
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// which is Unix time 1136239445. Since MST is GMT-0700,
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// the reference time can be thought of as
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// 01/02 03:04:05PM '06 -0700
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// To define your own format, write down what the reference time would look
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// like formatted your way; see the values of constants like ANSIC,
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// StampMicro or Kitchen for examples. The model is to demonstrate what the
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// reference time looks like so that the Format and Parse methods can apply
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// the same transformation to a general time value.
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//
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// Within the format string, an underscore _ represents a space that may be
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// replaced by a digit if the following number (a day) has two digits; for
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// compatibility with fixed-width Unix time formats.
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//
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// A decimal point followed by one or more zeros represents a fractional
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// second, printed to the given number of decimal places. A decimal point
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// followed by one or more nines represents a fractional second, printed to
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// the given number of decimal places, with trailing zeros removed.
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// When parsing (only), the input may contain a fractional second
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// field immediately after the seconds field, even if the layout does not
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// signify its presence. In that case a decimal point followed by a maximal
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// series of digits is parsed as a fractional second.
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//
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// Numeric time zone offsets format as follows:
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// -0700 ±hhmm
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// -07:00 ±hh:mm
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// Replacing the sign in the format with a Z triggers
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// the ISO 8601 behavior of printing Z instead of an
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// offset for the UTC zone. Thus:
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// Z0700 Z or ±hhmm
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// Z07:00 Z or ±hh:mm
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const (
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ANSIC = "Mon Jan _2 15:04:05 2006"
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UnixDate = "Mon Jan _2 15:04:05 MST 2006"
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RubyDate = "Mon Jan 02 15:04:05 -0700 2006"
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RFC822 = "02 Jan 06 15:04 MST"
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RFC822Z = "02 Jan 06 15:04 -0700" // RFC822 with numeric zone
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RFC850 = "Monday, 02-Jan-06 15:04:05 MST"
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RFC1123 = "Mon, 02 Jan 2006 15:04:05 MST"
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RFC1123Z = "Mon, 02 Jan 2006 15:04:05 -0700" // RFC1123 with numeric zone
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RFC3339 = "2006-01-02T15:04:05Z07:00"
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RFC3339Nano = "2006-01-02T15:04:05.999999999Z07:00"
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Kitchen = "3:04PM"
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// Handy time stamps.
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Stamp = "Jan _2 15:04:05"
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StampMilli = "Jan _2 15:04:05.000"
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StampMicro = "Jan _2 15:04:05.000000"
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StampNano = "Jan _2 15:04:05.000000000"
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)
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const (
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_ = iota
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stdLongMonth = iota + stdNeedDate // "January"
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stdMonth // "Jan"
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stdNumMonth // "1"
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stdZeroMonth // "01"
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stdLongWeekDay // "Monday"
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stdWeekDay // "Mon"
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stdDay // "2"
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stdUnderDay // "_2"
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stdZeroDay // "02"
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stdHour = iota + stdNeedClock // "15"
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stdHour12 // "3"
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stdZeroHour12 // "03"
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stdMinute // "4"
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stdZeroMinute // "04"
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stdSecond // "5"
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stdZeroSecond // "05"
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stdLongYear = iota + stdNeedDate // "2006"
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stdYear // "06"
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stdPM = iota + stdNeedClock // "PM"
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stdpm // "pm"
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stdTZ = iota // "MST"
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stdISO8601TZ // "Z0700" // prints Z for UTC
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stdISO8601ColonTZ // "Z07:00" // prints Z for UTC
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stdNumTZ // "-0700" // always numeric
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stdNumShortTZ // "-07" // always numeric
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stdNumColonTZ // "-07:00" // always numeric
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stdFracSecond0 // ".0", ".00", ... , trailing zeros included
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stdFracSecond9 // ".9", ".99", ..., trailing zeros omitted
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stdNeedDate = 1 << 8 // need month, day, year
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stdNeedClock = 2 << 8 // need hour, minute, second
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stdArgShift = 16 // extra argument in high bits, above low stdArgShift
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stdMask = 1<<stdArgShift - 1 // mask out argument
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)
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// std0x records the std values for "01", "02", ..., "06".
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var std0x = [...]int{stdZeroMonth, stdZeroDay, stdZeroHour12, stdZeroMinute, stdZeroSecond, stdYear}
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// nextStdChunk finds the first occurrence of a std string in
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// layout and returns the text before, the std string, and the text after.
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func nextStdChunk(layout string) (prefix string, std int, suffix string) {
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for i := 0; i < len(layout); i++ {
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switch c := int(layout[i]); c {
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case 'J': // January, Jan
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if len(layout) >= i+3 && layout[i:i+3] == "Jan" {
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if len(layout) >= i+7 && layout[i:i+7] == "January" {
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return layout[0:i], stdLongMonth, layout[i+7:]
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}
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return layout[0:i], stdMonth, layout[i+3:]
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}
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case 'M': // Monday, Mon, MST
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if len(layout) >= i+3 {
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if layout[i:i+3] == "Mon" {
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if len(layout) >= i+6 && layout[i:i+6] == "Monday" {
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return layout[0:i], stdLongWeekDay, layout[i+6:]
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}
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return layout[0:i], stdWeekDay, layout[i+3:]
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}
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if layout[i:i+3] == "MST" {
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return layout[0:i], stdTZ, layout[i+3:]
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}
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}
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case '0': // 01, 02, 03, 04, 05, 06
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if len(layout) >= i+2 && '1' <= layout[i+1] && layout[i+1] <= '6' {
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return layout[0:i], std0x[layout[i+1]-'1'], layout[i+2:]
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}
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case '1': // 15, 1
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if len(layout) >= i+2 && layout[i+1] == '5' {
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return layout[0:i], stdHour, layout[i+2:]
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}
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return layout[0:i], stdNumMonth, layout[i+1:]
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case '2': // 2006, 2
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if len(layout) >= i+4 && layout[i:i+4] == "2006" {
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return layout[0:i], stdLongYear, layout[i+4:]
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}
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return layout[0:i], stdDay, layout[i+1:]
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case '_': // _2
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if len(layout) >= i+2 && layout[i+1] == '2' {
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return layout[0:i], stdUnderDay, layout[i+2:]
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}
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case '3':
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return layout[0:i], stdHour12, layout[i+1:]
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case '4':
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return layout[0:i], stdMinute, layout[i+1:]
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case '5':
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return layout[0:i], stdSecond, layout[i+1:]
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case 'P': // PM
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if len(layout) >= i+2 && layout[i+1] == 'M' {
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return layout[0:i], stdPM, layout[i+2:]
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}
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case 'p': // pm
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if len(layout) >= i+2 && layout[i+1] == 'm' {
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return layout[0:i], stdpm, layout[i+2:]
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}
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case '-': // -0700, -07:00, -07
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if len(layout) >= i+5 && layout[i:i+5] == "-0700" {
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return layout[0:i], stdNumTZ, layout[i+5:]
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}
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if len(layout) >= i+6 && layout[i:i+6] == "-07:00" {
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return layout[0:i], stdNumColonTZ, layout[i+6:]
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}
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if len(layout) >= i+3 && layout[i:i+3] == "-07" {
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return layout[0:i], stdNumShortTZ, layout[i+3:]
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}
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case 'Z': // Z0700, Z07:00
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if len(layout) >= i+5 && layout[i:i+5] == "Z0700" {
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return layout[0:i], stdISO8601TZ, layout[i+5:]
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}
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if len(layout) >= i+6 && layout[i:i+6] == "Z07:00" {
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return layout[0:i], stdISO8601ColonTZ, layout[i+6:]
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}
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case '.': // .000 or .999 - repeated digits for fractional seconds.
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if i+1 < len(layout) && (layout[i+1] == '0' || layout[i+1] == '9') {
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ch := layout[i+1]
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j := i + 1
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for j < len(layout) && layout[j] == ch {
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j++
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}
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// String of digits must end here - only fractional second is all digits.
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if !isDigit(layout, j) {
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std := stdFracSecond0
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if layout[i+1] == '9' {
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std = stdFracSecond9
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}
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std |= (j - (i + 1)) << stdArgShift
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return layout[0:i], std, layout[j:]
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}
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}
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}
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}
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return layout, 0, ""
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}
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var longDayNames = []string{
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"Sunday",
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"Monday",
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"Tuesday",
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"Wednesday",
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"Thursday",
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"Friday",
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"Saturday",
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}
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var shortDayNames = []string{
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"Sun",
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"Mon",
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"Tue",
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"Wed",
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"Thu",
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"Fri",
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"Sat",
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}
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var shortMonthNames = []string{
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"---",
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"Jan",
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"Feb",
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"Mar",
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"Apr",
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"May",
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"Jun",
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"Jul",
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"Aug",
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"Sep",
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"Oct",
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"Nov",
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"Dec",
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}
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var longMonthNames = []string{
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"---",
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"January",
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"February",
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"March",
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"April",
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"May",
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"June",
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"July",
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"August",
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"September",
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"October",
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"November",
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"December",
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}
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// match returns true if s1 and s2 match ignoring case.
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// It is assumed s1 and s2 are the same length.
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func match(s1, s2 string) bool {
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for i := 0; i < len(s1); i++ {
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c1 := s1[i]
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c2 := s2[i]
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if c1 != c2 {
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// Switch to lower-case; 'a'-'A' is known to be a single bit.
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c1 |= 'a' - 'A'
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c2 |= 'a' - 'A'
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if c1 != c2 || c1 < 'a' || c1 > 'z' {
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return false
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}
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}
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}
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return true
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}
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func lookup(tab []string, val string) (int, string, error) {
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for i, v := range tab {
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if len(val) >= len(v) && match(val[0:len(v)], v) {
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return i, val[len(v):], nil
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}
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}
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return -1, val, errBad
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}
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// appendUint appends the decimal form of x to b and returns the result.
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// If x is a single-digit number and pad != 0, appendUint inserts the pad byte
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// before the digit.
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// Duplicates functionality in strconv, but avoids dependency.
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func appendUint(b []byte, x uint, pad byte) []byte {
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if x < 10 {
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if pad != 0 {
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b = append(b, pad)
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}
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return append(b, byte('0'+x))
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}
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if x < 100 {
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b = append(b, byte('0'+x/10))
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b = append(b, byte('0'+x%10))
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return b
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}
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var buf [32]byte
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n := len(buf)
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if x == 0 {
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return append(b, '0')
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}
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for x >= 10 {
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n--
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buf[n] = byte(x%10 + '0')
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x /= 10
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}
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n--
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buf[n] = byte(x + '0')
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return append(b, buf[n:]...)
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}
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// Never printed, just needs to be non-nil for return by atoi.
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var atoiError = errors.New("time: invalid number")
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// Duplicates functionality in strconv, but avoids dependency.
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func atoi(s string) (x int, err error) {
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neg := false
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if s != "" && s[0] == '-' {
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neg = true
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s = s[1:]
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}
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q, rem, err := leadingInt(s)
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x = int(q)
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if err != nil || rem != "" {
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return 0, atoiError
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}
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if neg {
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x = -x
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}
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return x, nil
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}
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// formatNano appends a fractional second, as nanoseconds, to b
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// and returns the result.
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func formatNano(b []byte, nanosec uint, n int, trim bool) []byte {
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u := nanosec
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var buf [9]byte
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for start := len(buf); start > 0; {
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start--
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buf[start] = byte(u%10 + '0')
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u /= 10
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}
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if n > 9 {
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n = 9
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}
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if trim {
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for n > 0 && buf[n-1] == '0' {
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n--
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}
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if n == 0 {
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return b
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}
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}
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b = append(b, '.')
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return append(b, buf[:n]...)
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}
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// String returns the time formatted using the format string
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// "2006-01-02 15:04:05.999999999 -0700 MST"
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func (t Time) String() string {
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return t.Format("2006-01-02 15:04:05.999999999 -0700 MST")
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}
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// Format returns a textual representation of the time value formatted
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// according to layout, which defines the format by showing how the reference
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// time,
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// Mon Jan 2 15:04:05 -0700 MST 2006
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// would be displayed if it were the value; it serves as an example of the
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// desired output. The same display rules will then be applied to the time
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// value.
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// Predefined layouts ANSIC, UnixDate, RFC3339 and others describe standard
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// and convenient representations of the reference time. For more information
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// about the formats and the definition of the reference time, see the
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// documentation for ANSIC and the other constants defined by this package.
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func (t Time) Format(layout string) string {
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var (
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name, offset, abs = t.locabs()
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year int = -1
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month Month
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day int
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hour int = -1
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min int
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sec int
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b []byte
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buf [64]byte
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)
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max := len(layout) + 10
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if max <= len(buf) {
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b = buf[:0]
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} else {
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b = make([]byte, 0, max)
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}
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// Each iteration generates one std value.
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for layout != "" {
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prefix, std, suffix := nextStdChunk(layout)
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if prefix != "" {
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b = append(b, prefix...)
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}
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if std == 0 {
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break
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}
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layout = suffix
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// Compute year, month, day if needed.
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if year < 0 && std&stdNeedDate != 0 {
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year, month, day, _ = absDate(abs, true)
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}
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// Compute hour, minute, second if needed.
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if hour < 0 && std&stdNeedClock != 0 {
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hour, min, sec = absClock(abs)
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}
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switch std & stdMask {
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case stdYear:
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y := year
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if y < 0 {
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y = -y
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}
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b = appendUint(b, uint(y%100), '0')
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case stdLongYear:
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// Pad year to at least 4 digits.
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y := year
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switch {
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case year <= -1000:
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b = append(b, '-')
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y = -y
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case year <= -100:
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b = append(b, "-0"...)
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y = -y
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case year <= -10:
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b = append(b, "-00"...)
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y = -y
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case year < 0:
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b = append(b, "-000"...)
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y = -y
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case year < 10:
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b = append(b, "000"...)
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case year < 100:
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b = append(b, "00"...)
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case year < 1000:
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b = append(b, '0')
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}
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b = appendUint(b, uint(y), 0)
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case stdMonth:
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b = append(b, month.String()[:3]...)
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case stdLongMonth:
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m := month.String()
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b = append(b, m...)
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case stdNumMonth:
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b = appendUint(b, uint(month), 0)
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case stdZeroMonth:
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b = appendUint(b, uint(month), '0')
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case stdWeekDay:
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b = append(b, absWeekday(abs).String()[:3]...)
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case stdLongWeekDay:
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s := absWeekday(abs).String()
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b = append(b, s...)
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case stdDay:
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b = appendUint(b, uint(day), 0)
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case stdUnderDay:
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b = appendUint(b, uint(day), ' ')
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case stdZeroDay:
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b = appendUint(b, uint(day), '0')
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case stdHour:
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b = appendUint(b, uint(hour), '0')
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case stdHour12:
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// Noon is 12PM, midnight is 12AM.
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hr := hour % 12
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if hr == 0 {
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hr = 12
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}
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b = appendUint(b, uint(hr), 0)
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case stdZeroHour12:
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// Noon is 12PM, midnight is 12AM.
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hr := hour % 12
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if hr == 0 {
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hr = 12
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}
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b = appendUint(b, uint(hr), '0')
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case stdMinute:
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b = appendUint(b, uint(min), 0)
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case stdZeroMinute:
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b = appendUint(b, uint(min), '0')
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case stdSecond:
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b = appendUint(b, uint(sec), 0)
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case stdZeroSecond:
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b = appendUint(b, uint(sec), '0')
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case stdPM:
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if hour >= 12 {
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b = append(b, "PM"...)
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} else {
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b = append(b, "AM"...)
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}
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case stdpm:
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if hour >= 12 {
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b = append(b, "pm"...)
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} else {
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b = append(b, "am"...)
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}
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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".
|
|
if offset == 0 && (std == stdISO8601TZ || std == stdISO8601ColonTZ) {
|
|
b = append(b, 'Z')
|
|
break
|
|
}
|
|
zone := offset / 60 // convert to minutes
|
|
if zone < 0 {
|
|
b = append(b, '-')
|
|
zone = -zone
|
|
} else {
|
|
b = append(b, '+')
|
|
}
|
|
b = appendUint(b, uint(zone/60), '0')
|
|
if std == stdISO8601ColonTZ || std == stdNumColonTZ {
|
|
b = append(b, ':')
|
|
}
|
|
b = appendUint(b, uint(zone%60), '0')
|
|
case stdTZ:
|
|
if name != "" {
|
|
b = append(b, name...)
|
|
break
|
|
}
|
|
// 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 {
|
|
b = append(b, '-')
|
|
zone = -zone
|
|
} else {
|
|
b = append(b, '+')
|
|
}
|
|
b = appendUint(b, uint(zone/60), '0')
|
|
b = appendUint(b, uint(zone%60), '0')
|
|
case stdFracSecond0, stdFracSecond9:
|
|
b = formatNano(b, uint(t.Nanosecond()), std>>stdArgShift, std&stdMask == stdFracSecond9)
|
|
}
|
|
}
|
|
return string(b)
|
|
}
|
|
|
|
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 value, errBad
|
|
}
|
|
prefix = cutspace(prefix)
|
|
value = cutspace(value)
|
|
continue
|
|
}
|
|
if len(value) == 0 || value[0] != prefix[0] {
|
|
return value, 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 how the reference time,
|
|
// Mon Jan 2 15:04:05 -0700 MST 2006
|
|
// would be interpreted if it were the value; it serves as an example of
|
|
// the input format. The same interpretation will then be made to the
|
|
// input string.
|
|
// Predefined layouts ANSIC, UnixDate, RFC3339 and others describe standard
|
|
// and convenient representations of the reference time. For more information
|
|
// about the formats and the definition of the reference time, see the
|
|
// documentation for ANSIC and the other constants defined by this package.
|
|
//
|
|
// 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 (note that because the year is
|
|
// 0, this time is before the zero Time).
|
|
// Years must be in the range 0000..9999. The day of the week is checked
|
|
// for syntax but it is otherwise ignored.
|
|
//
|
|
// In the absence of a time zone indicator, Parse returns a time in UTC.
|
|
//
|
|
// When parsing a time with a zone offset like -0700, if the offset corresponds
|
|
// to a time zone used by the current location (Local), then Parse uses that
|
|
// location and zone in the returned time. Otherwise it records the time as
|
|
// being in a fabricated location with time fixed at the given zone offset.
|
|
//
|
|
// When parsing a time with a zone abbreviation like MST, if the zone abbreviation
|
|
// has a defined offset in the current location, then that offset is used.
|
|
// The zone abbreviation "UTC" is recognized as UTC regardless of location.
|
|
// If the zone abbreviation is unknown, Parse records the time as being
|
|
// in a fabricated location with the given zone abbreviation and a zero offset.
|
|
// This choice means that such a time can be parse and reformatted with the
|
|
// same layout losslessly, but the exact instant used in the representation will
|
|
// differ by the actual zone offset. To avoid such problems, prefer time layouts
|
|
// that use a numeric zone offset, or use ParseInLocation.
|
|
func Parse(layout, value string) (Time, error) {
|
|
return parse(layout, value, UTC, Local)
|
|
}
|
|
|
|
// ParseInLocation is like Parse but differs in two important ways.
|
|
// First, in the absence of time zone information, Parse interprets a time as UTC;
|
|
// ParseInLocation interprets the time as in the given location.
|
|
// Second, when given a zone offset or abbreviation, Parse tries to match it
|
|
// against the Local location; ParseInLocation uses the given location.
|
|
func ParseInLocation(layout, value string, loc *Location) (Time, error) {
|
|
return parse(layout, value, loc, loc)
|
|
}
|
|
|
|
func parse(layout, value string, defaultLocation, local *Location) (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)
|
|
stdstr := layout[len(prefix) : len(layout)-len(suffix)]
|
|
value, err = skip(value, prefix)
|
|
if err != nil {
|
|
return Time{}, &ParseError{alayout, avalue, prefix, value, ""}
|
|
}
|
|
if std == 0 {
|
|
if len(value) != 0 {
|
|
return Time{}, &ParseError{alayout, avalue, "", value, ": extra text: " + value}
|
|
}
|
|
break
|
|
}
|
|
layout = suffix
|
|
var p string
|
|
switch std & stdMask {
|
|
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)
|
|
std &= stdMask
|
|
if std == stdFracSecond0 || std == stdFracSecond9 {
|
|
// 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 == stdISO8601TZ || std == stdISO8601ColonTZ) && 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
|
|
|
|
case stdFracSecond0:
|
|
// stdFracSecond0 requires the exact number of digits as specified in
|
|
// the layout.
|
|
ndigit := 1 + (std >> stdArgShift)
|
|
if len(value) < ndigit {
|
|
err = errBad
|
|
break
|
|
}
|
|
nsec, rangeErrString, err = parseNanoseconds(value, ndigit)
|
|
value = value[ndigit:]
|
|
|
|
case stdFracSecond9:
|
|
if len(value) < 2 || value[0] != '.' || value[1] < '0' || '9' < value[1] {
|
|
// Fractional second omitted.
|
|
break
|
|
}
|
|
// Take any number of digits, even more than asked for,
|
|
// because it is what the stdSecond case would do.
|
|
i := 0
|
|
for i < 9 && i+1 < len(value) && '0' <= value[i+1] && value[i+1] <= '9' {
|
|
i++
|
|
}
|
|
nsec, rangeErrString, err = parseNanoseconds(value, 1+i)
|
|
value = value[1+i:]
|
|
}
|
|
if rangeErrString != "" {
|
|
return Time{}, &ParseError{alayout, avalue, stdstr, value, ": " + rangeErrString + " out of range"}
|
|
}
|
|
if err != nil {
|
|
return Time{}, &ParseError{alayout, avalue, stdstr, value, ""}
|
|
}
|
|
}
|
|
if pmSet && hour < 12 {
|
|
hour += 12
|
|
} else if amSet && hour == 12 {
|
|
hour = 0
|
|
}
|
|
|
|
if z != nil {
|
|
return Date(year, Month(month), day, hour, min, sec, nsec, z), nil
|
|
}
|
|
|
|
if zoneOffset != -1 {
|
|
t := Date(year, Month(month), day, hour, min, sec, nsec, UTC)
|
|
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 != "" {
|
|
t := Date(year, Month(month), day, hour, min, sec, nsec, UTC)
|
|
// 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, t.sec+internalToUnix)
|
|
if ok {
|
|
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 default.
|
|
return Date(year, Month(month), day, hour, min, sec, nsec, defaultLocation), nil
|
|
}
|
|
|
|
func parseNanoseconds(value string, nbytes int) (ns int, rangeErrString string, err error) {
|
|
if value[0] != '.' {
|
|
err = errBad
|
|
return
|
|
}
|
|
if ns, err = atoi(value[1:nbytes]); 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 int64, rem string, err error) {
|
|
i := 0
|
|
for ; i < len(s); i++ {
|
|
c := s[i]
|
|
if c < '0' || c > '9' {
|
|
break
|
|
}
|
|
if x >= (1<<63-10)/10 {
|
|
// overflow
|
|
return 0, "", errLeadingInt
|
|
}
|
|
x = x*10 + int64(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 int64
|
|
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
|
|
}
|