Something like python timedelta in golang - go

Question

I want to get a datetime, counting weeks from a date, days from a week and seconds from 00:00 time.
With Python I can use this:
BASE_TIME = datetime.datetime(1980,1,6,0,0)
tdelta = datetime.timedelta(weeks = 1722,
days = 1,
seconds = 66355)
mydate = BASE_DATE + tdelta
I'm trying to get it with Go, but I have some problems to reach it:
package main
import (
"fmt"
"time"
)
var base = time.Date(1980, 1, 6, 0, 0, 0, 0, time.UTC)
func main() {
weeks := 1722
days := 1
seconds := 66355
weeksToSecs := 7 * 24 * 60 * 60
daysToSecs := 24 * 60 * 60
totalSecs := (weeks * weeksToSecs) + (days * daysToSecs) + seconds
nanosecs := int64(totalSecs) * 1000000000
//delta := time.Date(0, 0, 0, 0, 0, totalSecs, 0, time.UTC)
date := base.Add(nanosecs)
fmt.Printf("Result: %s", date)
}
prog.go:21: cannot use nanosecs (type int64) as type time.Duration in function argument
http://play.golang.org/p/XWSK_QaXrQ
What I'm missing?Thanks

Answer 1

package main
import (
"fmt"
"time"
)
func main() {
baseTime := time.Date(1980, 1, 6, 0, 0, 0, 0, time.UTC)
date := baseTime.Add(1722*7*24*time.Hour + 24*time.Hour + 66355*time.Second)
fmt.Println(date)
}
Playground
Output
2013-01-07 18:25:55 +0000 UTC

Answer 2

jnml's answer works and is more idiomatic go. But to illustrate why your original code didn't work, all you have to do is change one line.
date := base.Add(time.Duration(nanosecs)) will cast the nanosecs to a time.Duration which is the type that Add expects as opposed to int64. Go will not automatically cast a type for you so it complained about the type being int64.

Answer 3

timeutil supports timedelta and strftime.
package main
import (
"fmt"
"time"
"github.com/leekchan/timeutil"
)
func main() {
base := time.Date(2015, 2, 3, 0, 0, 0, 0, time.UTC)
td := timeutil.Timedelta{Days: 10, Minutes: 17, Seconds: 56}
result := base.Add(td.Duration())
fmt.Println(result) // "2015-02-13 00:17:56 +0000 UTC"
}