78 lines
1.6 KiB
Go
78 lines
1.6 KiB
Go
package typeutils
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// CTORS BEGIN
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func Some[T any](value T) Optional[T] {
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return Optional[T]{value, true}
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}
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func None[T any]() Optional[T] {
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return Optional[T]{present: false}
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}
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// Because None has no type passing a value of desired type might be preferred syntax over providing type on the function call
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func None_t[T any](T) Optional[T] {
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return Optional[T]{present: false}
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}
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// CTORS END
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func (opt Optional[T]) IsSome() bool { return opt.present }
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func (opt Optional[T]) IsNone() bool { return !opt.present }
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func (opt Optional[T]) HasValue() bool { return opt.IsSome() }
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// UNWRAPPABLE INTERFACE BEGIN
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func (opt Optional[T]) Expect(msg string) T {
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if opt.present {
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return opt.value
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}
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panic(msg)
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}
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func (opt Optional[T]) Unwrap() T {
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if opt.present {
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return opt.value
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}
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panic("Tried unwrapping an Optional that did not have a value!")
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}
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func (opt Optional[T]) UnwrapOr(val T) T {
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if opt.present {
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return opt.value
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}
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return val
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}
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func (opt Optional[T]) UnwrapOrDefault() T {
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if opt.present {
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return opt.value
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}
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var res T
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return res
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}
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func (opt Optional[T]) UnwrapOrElse(f func() T) T {
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if opt.present {
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return opt.value
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}
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return f()
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}
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// UNWRAPPABLE INTERFACE END
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// transforms Some(v) to Ok(v), and None to Err(err)
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func (opt Optional[T]) OkOr(err error) Result[T] {
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if opt.present {
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return Ok(opt.value)
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}
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return Err[T](err)
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}
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// transforms Some(v) to Ok(v), and None to a value of Err using the provided function
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func (opt Optional[T]) OkOrElse(f func() error) Result[T] {
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if opt.present {
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return Ok(opt.value)
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}
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return Err[T](f())
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}
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