refactor(Type)!: harmonize naming 1

type/optional.go

@@ -0,0 +1,108 @@
+package Type
+
+import "github.com/lbatuska/goutils/assert"
+
+// CTORS BEGIN
+func Some[T any](value T) Optional[T] {
+	return Optional[T]{value, true}
+}
+
+func None[T any]() Optional[T] {
+	return Optional[T]{present: false}
+}
+
+// Because None has no type passing a value of desired type might be preferred syntax over providing type on the function call
+func None_t[T any](T) Optional[T] {
+	return Optional[T]{present: false}
+}
+
+// CTORS END
+
+func (opt *Optional[T]) IsSome() bool {
+	if opt == nil {
+		return false
+	}
+	return opt.present
+}
+
+func (opt *Optional[T]) IsNone() bool {
+	if opt == nil {
+		return true
+	}
+	return !opt.present
+}
+
+func (opt *Optional[T]) HasValue() bool {
+	if opt == nil {
+		return false
+	}
+	return opt.IsSome()
+}
+
+// UNWRAPPABLE INTERFACE BEGIN
+func (opt *Optional[T]) Expect(msg string) T {
+	assert.NotNil(opt)
+	if opt.present {
+		return opt.value
+	}
+	panic(msg)
+}
+
+func (opt *Optional[T]) Unwrap() T {
+	assert.NotNil(opt)
+	if opt.present {
+		return opt.value
+	}
+	panic("Tried unwrapping an Optional that did not have a value!")
+}
+
+func (opt *Optional[T]) UnwrapOr(val T) T {
+	if opt != nil {
+		if opt.present {
+			return opt.value
+		}
+	}
+	return val
+}
+
+func (opt *Optional[T]) UnwrapOrDefault() T {
+	if opt != nil {
+		if opt.present {
+			return opt.value
+		}
+	}
+	var res T
+	return res
+}
+
+func (opt *Optional[T]) UnwrapOrElse(f func() T) T {
+	if opt != nil {
+		if opt.present {
+			return opt.value
+		}
+	}
+	return f()
+}
+
+// UNWRAPPABLE INTERFACE END
+
+// transforms Some(v) to Ok(v), and None to Err(err)
+func (opt *Optional[T]) OkOr(err error) Result[T] {
+	if opt != nil {
+		if opt.present {
+			return Ok(opt.value)
+		}
+	}
+
+	return Err[T](err)
+}
+
+// transforms Some(v) to Ok(v), and None to a value of Err using the provided function
+func (opt *Optional[T]) OkOrElse(f func() error) Result[T] {
+	if opt != nil {
+		if opt.present {
+			return Ok(opt.value)
+		}
+	}
+	return Err[T](f())
+}