32 lines
637 B
Go
32 lines
637 B
Go
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package ucontainer
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// Optional is an optional value.
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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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// Value returns the value and true if the value exists. If not, it returns the
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// last set value and false.
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func (this *Optional[T]) Value () (T, bool) {
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return this.value, this.exists
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}
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// Set sets the value.
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func (this *Optional[T]) Set (value T) {
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this.value = value
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this.exists = true
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}
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// Unset unsets the value.
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func (this *Optional[T]) Unset () {
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var zero T
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this.value = zero
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this.exists = false
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}
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// Exists returns if the value is currently set.
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func (this *Optional[T]) Exists () bool {
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return this.exists
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}
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