Created
May 26, 2018 01:50
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Satisfying interfaces in Go using struct members and packages
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| package main | |
| import "time" | |
| type Time interface { | |
| Now() time.Time | |
| } | |
| type fakeTime struct { | |
| Now func() time.Time | |
| } | |
| func main() { | |
| // Why don't struct members staisfy interfaces? | |
| t := &fakeTime{ | |
| Now: func() time.Time { | |
| return time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC) | |
| }, | |
| } | |
| new(fakeTime).(Time) | |
| // ./main.go:20:15: invalid type assertion: new(fakeTime).(Time) (non-interface type *fakeTime on left) | |
| // Why don't packages satisfy interfaces? | |
| time.(Time) | |
| // ./main.go:24:6: use of package time without selector | |
| } |
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