40 lines
911 B
Go
40 lines
911 B
Go
package opt
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import (
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"encoding/json"
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"github.com/reiver/go-erorr"
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)
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const errNilReceiver = erorr.Error("opt: nil receiver")
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var _ json.Unmarshaler = new(Optional[bool])
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var _ json.Unmarshaler = new(Optional[string])
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// UnmarshalJSON makes it so json.Unmarshaler is implemented.
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func (receiver *Optional[T]) UnmarshalJSON(data []byte) error {
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if nil == receiver {
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return errNilReceiver
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}
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switch interface{}(&receiver.value).(type) {
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case *bool, *int64, *uint64, *string, *json.Number, json.Unmarshaler:
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// these are OK.
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default:
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return erorr.Errorf("opt: cannot unmarshal into something of type %T from JSON because pointer to parameterized type is ‘%T’ rather than ‘*bool’, ‘*string’, or ‘json.Unmarshaler’", receiver, &receiver.value)
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}
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{
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var dst T
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err := json.Unmarshal(data, &dst)
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if nil != err {
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return err
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}
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*receiver = Something(dst)
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}
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return nil
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}
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