add documentation

pkg/libyear/libyear.go

@@ -5,17 +5,20 @@ import (
 	"time"
 )
 
+// Info defines a version and a commit time for that version
 type Info struct {
 	Version string    // version string
 	Time    time.Time // commit time
 }
 
+// Pair is a set of versions for a dependency (current and newest possible)
 type Pair struct {
 	Name    string
 	Latest  Info
 	Current Info
 }
 
+// Calc returns the summed time distance (as a time.Duration) between a set of Pairs of modules.
 // TODO: sum can only represent ~290 years before overflowing, but we don't actually need nanosecond precision!
 // Probably worth switching to hour-based summing here.
 func Calc(p ...Pair) time.Duration {
@@ -26,6 +29,7 @@ func Calc(p ...Pair) time.Duration {
 	return sum
 }
 
+// DecimalYear conversts a time.Duration (which is in nsec) to a two-decimal-place count of years.
 func DecimalYear(d time.Duration) string {
 	return fmt.Sprintf("%.2f", float64(d.Truncate(time.Hour)/time.Hour)/float64(8760))
 }