Documentation
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Index ¶
- Constants
- func Add(t time.Time, d Duration) time.Time
- func AddMicros(t time.Time, d int64) time.Time
- func DiffMicros(t1, t2 time.Time) int64
- func Truncate(d time.Duration, r time.Duration) time.Duration
- type Duration
- func Decode(sortNanos int64, months int64, days int64) (Duration, error)
- func DecodeDuration(months, days, nanos int64) Duration
- func FromBigInt(src *big.Int) (Duration, bool)
- func FromFloat64(x float64) Duration
- func FromInt64(x int64) Duration
- func MakeDuration(nanos, days, months int64) Duration
- func MakeNormalizedDuration(nanos, days, months int64) Duration
- func (d Duration) Add(x Duration) Duration
- func (d Duration) AsBigInt(dst *big.Int)
- func (d Duration) AsFloat64() float64
- func (d Duration) AsInt64() (int64, bool)
- func (d Duration) Compare(x Duration) int
- func (d Duration) Div(x int64) Duration
- func (d Duration) DivFloat(x float64) Duration
- func (d Duration) Encode() (sortNanos int64, months int64, days int64, err error)
- func (d Duration) EncodeBigInt() (sortNanos *big.Int, months int64, days int64)
- func (d Duration) Format(buf *bytes.Buffer)
- func (d Duration) Mul(x int64) Duration
- func (d Duration) MulFloat(x float64) Duration
- func (d Duration) Nanos() int64
- func (d *Duration) SetNanos(nanos int64)
- func (d Duration) String() string
- func (d Duration) StringNanos() string
- func (d Duration) Sub(x Duration) Duration
Constants ¶
const ( // MicrosPerMilli is the amount of microseconds in a millisecond. MicrosPerMilli = 1000 // MillisPerSec is the amount of seconds in a millisecond. MillisPerSec = 1000 // SecsPerMinute is the amount of seconds in a minute. SecsPerMinute = 60 // SecsPerHour is the amount of seconds in an hour. SecsPerHour = 3600 // SecsPerDay is the amount of seconds in a day. SecsPerDay = 86400 // DaysPerMonth is the assumed amount of days in a month. // is always evaluated to 30, as it is in postgres. DaysPerMonth = 30 // DaysPerYear is the number of days in a year. // It is assumed to include a quarter day to account for the leap year. // Matches DAYS_PER_YEAR in postgres. DaysPerYear = 365.25 // MonthsPerYear is the amount of months in the year. MonthsPerYear = 12 )
Variables ¶
This section is empty.
Functions ¶
func AddMicros ¶
AddMicros adds the microsecond delta to the provided time value. The reason this function is necessary even though time.Add(duration) exists is that time.Duration can only hold values up to ~290 years, because it stores duration at the nanosecond resolution. This function makes it possible to add more than 290 years to a time.Time, at the tradeoff of working on a microsecond resolution.
func DiffMicros ¶
DiffMicros computes the microsecond difference between two time values. The reason this function is necessary even though time.Sub(time) exists is that time.Duration can only hold values up to ~290 years, because it stores duration at the nanosecond resolution. This function should be used if a difference of more than 290 years is possible between time values, and a microsecond resolution is acceptable.
Types ¶
type Duration ¶
A Duration represents a length of time.
A duration of "1 month" cannot be represented as a fixed number of nanoseconds because the length of months vary. The same is true for days because of leap seconds. Given a begin or end time to anchor a duration, the nanosecond count can be calculated, but it's useful to represent durations such as "1 year 3 months" without an anchor. Duration allows this.
For the purposes of Compare and Encode, 1 month is considered equivalent to 30 days and 1 day is equivalent to 24 * 60 * 60 * 1E9 nanoseconds.
Although the Nanos field is a number of nanoseconds, all operations round to the nearest microsecond. Any setting of this field should avoid setting with precision below microseconds. The only exceptions are the encode/decode operations.
TODO(dan): Until the overflow and underflow handling is fixed, this is only useful for durations of < 292 years.
func Decode ¶
Decode reverses the three integers returned from Encode and produces an equal Duration to the original.
func DecodeDuration ¶
DecodeDuration returns a Duration without rounding nanos.
func FromBigInt ¶
FromBigInt converts a big.Int number of nanoseconds to a duration. Inverse conversion of AsBigInt. Boolean false if the result overflows.
func FromFloat64 ¶
FromFloat64 converts a float64 number of seconds to a duration. Inverse conversion of AsFloat64.
func FromInt64 ¶
FromInt64 converts an int64 number of seconds to a duration. Inverse conversion of AsInt64.
func MakeDuration ¶
MakeDuration returns a Duration rounded to the nearest microsecond.
func MakeNormalizedDuration ¶
MakeNormalizedDuration returns a normalized Duration.
func (Duration) AsBigInt ¶
AsBigInt converts a duration to a big.Int with the number of nanoseconds.
func (Duration) AsInt64 ¶
AsInt64 converts a duration to an int64 number of seconds. The conversion may overflow, in which case the boolean return value is false.
func (Duration) Compare ¶
Compare returns an integer representing the relative length of two Durations. The result will be 0 if d==x, -1 if d < x, and +1 if d > x.
func (Duration) Encode ¶
Encode returns three integers such that the original Duration is recoverable (using Decode) and the first int will approximately sort a collection of encoded Durations.
func (Duration) EncodeBigInt ¶
EncodeBigInt is the same as Encode, except that it always returns successfully and is slower.
func (Duration) Format ¶
Format emits a string representation of a Duration to a Buffer truncated to microseconds.
func (Duration) StringNanos ¶
StringNanos returns a string representation of a Duration including its hidden nanoseconds value. To be used only by the encoding/decoding packages for pretty printing of on-disk values.
Source Files