32 lines
697 B
Go
32 lines
697 B
Go
package ucontainer
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// Optional can either hold a value, or nothing.
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type Optional[T any] struct {
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value T
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exists bool
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}
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// O creates a new optional with the specified value.
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func O[T any] (value T) Optional[T] {
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return Optional[T] {
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value: value,
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exists: true,
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}
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}
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// Void returns an optional with no value.
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func Void[T any] () Optional[T] {
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return Optional[T] { }
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}
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// Exists returns if the value is currently set.
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func (optional Optional[T]) Exists () bool {
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return optional.exists
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}
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// Value returns the value and true if the value exists. If not, it returns the
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// zero value and false.
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func (optional Optional[T]) Value () (T, bool) {
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return optional.value, optional.exists
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}
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