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package types
import (
"bytes"
"encoding/json"
)
type Option[T any] struct {
Set bool
Valid bool
Value T
}
func (s Option[T]) MarshalJSON() ([]byte, error) {
if !s.Valid {
return []byte("null"), nil
}
return json.Marshal(s.Value)
}
func (s *Option[T]) UnmarshalJSON(data []byte) error {
s.Set = true
s.Valid = false
if bytes.Equal(data, []byte("null")) {
// The key was set to null, set value to zero/default value
var zero T
s.Value = zero
return nil
}
// The key isn't set to null
var v T
if err := json.Unmarshal(data, &v); err != nil {
return err
}
s.Value = v
s.Valid = true
return nil
}