True when u is a Driver bundle.
export const const isDriver: <
S extends Spec = Spec,
R = unknown
>(
u: unknown
) => u is Driver<S, R>
True when u is a
Driver
bundle.
isDriver = <function (type parameter) S in <S extends Spec = Spec, R = unknown>(u: unknown): u is Driver<S, R>S extends Spec = Spec, function (type parameter) R in <S extends Spec = Spec, R = unknown>(u: unknown): u is Driver<S, R>R = unknown>(
u: unknownu: unknown,
): u: unknownu is interface Driver<S extends Spec, R>A HyperService impl before worker-context discharge — the impl still carries requirement R on its
Effect methods, paired with the
Context.Context
captured at build time. Used by
WorkPool
,
Gate
, and
Daemon
(any toolkit HyperService that builds
its driver under ambient R).
layer
/
serve
grant locally via
grantLocal
;
serveRemote
defers discharge to each wire call via
invokeWireMethodWithContext
so
one materialization backs both paths.
Driver<function (type parameter) S in <S extends Spec = Spec, R = unknown>(u: unknown): u is Driver<S, R>S, function (type parameter) R in <S extends Spec = Spec, R = unknown>(u: unknown): u is Driver<S, R>R> => import PredicatePredicate.const hasProperty: <typeof driverSym>(self: unknown, property: typeof driverSym) => self is { [K in typeof driverSym]: unknown; } (+1 overload)Checks whether a value has a given property key.
When to use
Use when you need a Predicate guard for property access on unknown
values with a simple structural object check.
Details
Uses the in operator and isObjectKeyword. This does not check property
value types.
Example (Guarding object properties)
import { Predicate } from "effect"
const hasName = Predicate.hasProperty("name")
const data: unknown = { name: "Ada" }
if (hasName(data)) {
console.log(data.name)
}
hasProperty(u: unknownu, const driverSym: typeof driverSymRuntime marker for a
Driver
bundle.
driverSym);