Maybe

Maybe defines an explicit business contract to represent a present entity (some) or an absent one (none) without exposing null/undefined in the domain.

Example

Syntax

Maybe type

type Maybe<Entity extends C.Entity> =
	| C.Some<Entity>
	| C.None<C.GetKindValue<typeof C.entityKind, Entity>>

some constructor

function some<Entity extends C.Entity>(
	entity: Entity
): C.Some<Entity>

none constructor

function none<EntityName extends string>(
	entityName: EntityName
): C.None<EntityName>

Parameters

• entity: valid business entity to wrap in the "present" branch.
• entityName: business entity name used to build the typed "absent" branch.

Return value

• some(entity) returns a C.Some<Entity>.
• none(name) returns a C.None<name>.
• both satisfy the C.Maybe<Entity> contract when the entity name matches.

Why this matters in business code

The Maybe type lets you define a use-case contract before implementation details:

• found result is explicitly typed with some(...)
• missing result is explicitly typed with none(...)
• the domain contract stays readable and stable.

See also

• entity
• unwrapEntity
• useCase