Context.Reference<boolean>Context reference that controls whether the runtime should bypass scheduler
yield checks. When set to true, the fiber run loop won't call
Scheduler.shouldYield.
When to use
Use to bypass scheduler yield checks for controlled runtime workloads where cooperative yielding should be disabled.
Gotchas
Setting this reference to true can let long-running fibers monopolize the
JavaScript thread.
export const const PreventSchedulerYield: Context.Reference<boolean>const PreventSchedulerYield: {
defaultValue: () => Shape;
of: (this: void, self: boolean) => boolean;
context: (self: boolean) => Context.Context<never>;
use: (f: (service: boolean) => Effect<A, E, R>) => Effect<A, E, R>;
useSync: (f: (service: boolean) => A) => Effect<A, never, never>;
Identifier: Identifier;
Service: Shape;
key: string;
stack: string | undefined;
pipe: { <A>(this: A): A; <A, B = never>(this: A, ab: (_: A) => B): B; <A, B = never, C = never>(this: A, ab: (_: A) => B, bc: (_: B) => C): C; <A, B = never, C = never, D = never>(this: A, ab: (_: A) => B, bc: (_: B) => C, cd: (_: C) => D): D; <…;
toString: () => string;
toJSON: () => unknown;
}
Context reference that controls whether the runtime should bypass scheduler
yield checks. When set to true, the fiber run loop won't call
Scheduler.shouldYield.
When to use
Use to bypass scheduler yield checks for controlled runtime workloads where
cooperative yielding should be disabled.
Gotchas
Setting this reference to true can let long-running fibers monopolize the
JavaScript thread.
PreventSchedulerYield = import ContextContext.const Reference: <Service>(
key: string,
options: {
readonly defaultValue: () => Service
}
) => Reference<Service>
Creates a context key with a default value.
When to use
Use when you need to define a context key with a lazily computed default
value.
Details
Context.Reference allows you to create a key that can hold a value. You
can provide a default value for the service, which will automatically be used
when the context is accessed, or override it with a custom implementation
when needed. The default value is computed lazily and cached on the
reference.
Example (Creating references with default values)
import { Context } from "effect"
// Create a reference with a default value
const LoggerRef = Context.Reference("Logger", {
defaultValue: () => ({ log: (msg: string) => console.log(msg) })
})
// The reference provides the default value when accessed from an empty context
const context = Context.empty()
const logger = Context.get(context, LoggerRef)
// You can also override the default value
const customContext = Context.make(LoggerRef, {
log: (msg: string) => `Custom: ${msg}`
})
const customLogger = Context.get(customContext, LoggerRef)
Reference<boolean>("effect/Scheduler/PreventSchedulerYield", {
defaultValue: () => booleandefaultValue: () => false
})