ContextHas

zio.blocks.context.ContextHas

See theContextHas companion object

trait ContextHas[Ctx, A]

Compile-time evidence that a context of type Ctx provides all types in A.

Resolves when Ctx <: A. For intersection types this means every component of A must appear in Ctx:

// resolves: (Server & Database & Logger) &lt;: (Database & Logger)
implicitly[ContextHas[Server & Database & Logger, Database & Logger]]

// fails:   (Server & Database) is not &lt;: (Database & Logger)
implicitly[ContextHas[Server & Database, Database & Logger]]
// → "Context[Server & Database] does not provide Database & Logger.
//    Compare the two types — each component of Database & Logger
//    not in Server & Database must be added via context.add(value)."

Typical usage — one implicit checks everything:

def serve[ReqCtx, Ctx](routes: Routes[ReqCtx], context: Context[Ctx])(implicit
 ev: ContextHas[Ctx, ReqCtx & Server]
): ServerHandle = ???

Attributes

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

trait Matchable

class Any

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