38 lines
627 B
Go
38 lines
627 B
Go
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package optional
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// Optional represents a generic optional type, stored as an interface{}.
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type Interface struct {
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isSet bool
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value interface{}
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}
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func NewInterface(value interface{}) Interface {
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return Interface{
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true,
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value,
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}
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}
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// EmptyInterface returns a new Interface that does not have a value set.
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func EmptyInterface() Interface {
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return Interface{
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false,
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nil,
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}
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}
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func (b Interface) IsSet() bool {
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return b.isSet
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}
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func (b Interface) Value() interface{} {
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return b.value
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}
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func (b Interface) Default(defaultValue interface{}) interface{} {
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if b.isSet {
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return b.value
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}
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return defaultValue
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}
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