Wire

zio.blocks.scope.Wire

See theWire companion object

sealed trait Wire[-In, +Out]

A recipe for constructing a service and its dependencies.

Wires are the building blocks of dependency injection in Scope. They describe how to construct a service given access to its dependencies via a context.

==Wire Types==

Wire.Shared: Converted to a reference-counted Resource.shared (default)
Wire.Unique: Converted to a fresh Resource.unique each time

==Creating Wires==

Use Wire.shared[T] and Wire.unique[T] macros for automatic derivation from constructors, or create wires manually for custom construction logic.

==Usage Example==

// Define a service with its wire
class Database(config: Config)
object Database {
 val wire: Wire[Config, Database] = Wire.shared[Database]
}

// Create a unique wire for request-scoped services
class RequestHandler(db: Database)
object RequestHandler {
 val wire: Wire[Database, RequestHandler] = Wire.unique[RequestHandler]
}

// Create a Resource from wires
val appResource = Resource.from[App](
 Wire(Config("localhost", 8080)),
 Wire.shared[Database]
)

Type parameters

In: the dependencies required (contravariant - accepts supertypes)
Out: the service(s) produced (covariant - produces subtypes)

Attributes

Companion: object
Source: Wire.scala
Graph
Supertypes: class Object

trait Matchable

class Any
Known subtypes: class Shared[In, Out]

class Unique[In, Out]

Members list

Value members

Abstract methods

Returns true if this wire is shared (reference-counted via Resource.shared).

Shared wires are converted to Resource.shared, meaning allocations may share a single underlying instance across scopes. The instance is released when the last referencing scope is closed.

Attributes

Returns: true if this wire is shared, false if unique
Source: Wire.scala

Converts this wire to a shared wire.

If already shared, returns this. Otherwise, creates a new Wire.Shared wire with the same construction function.

Attributes

Returns: a shared version of this wire
Source: Wire.scala

Converts this Wire to a Resource by providing resolved dependencies.

Value parameters

deps: Context containing all required dependencies

Attributes

Returns: a Resource that creates Out values
Source: Wire.scala

Converts this wire to a unique wire.

If already unique, returns this. Otherwise, creates a new Wire.Unique wire with the same construction function.

Attributes

Returns: a unique version of this wire
Source: Wire.scala

Concrete methods

Returns true if this wire is unique (creates fresh instances each time).

Unique wires create a new instance for each dependent service.

Attributes

Returns: true if this wire is unique, false if shared
Source: Wire.scala

Inherited and Abstract methods

Constructs the service using the given scope and context.

The scope is used to register finalizers (e.g. for AutoCloseable services), while the context provides access to dependencies required by this wire.

Value parameters

ctx: the context providing dependencies
scope: the scope for cleanup registration

Attributes

Returns: the constructed service
Inherited from:: WireVersionSpecific (hidden)
Source: WireVersionSpecific.scala

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