package fiber

You can search for identifiers within the package.

in-package search v0.2.0

On This Page

Fiber cancellation

fiber
- Fiber
  - Cancel
  - Expert
  - Ivar
  - Make_map_traversals
    
    Map
    
    Multi
  - Mutex
  - Mvar
  - O
  - Pool
  - Scheduler
  - Stream
    
    In
    
    Out
  - Svar
  - Throttle
  - Var

Legend:
Library
Module
Module type
Parameter
Class
Class type

Fiber cancellation

This module provides a way to cancel long running computations. Cancellation is fully explicit and fibers must explicitly check for it at strategic points.

type t

val create : unit -> t

val fire : t -> unit fiber

Activate a cancellation request.

fire is idempotent, so calling fire t more than once has no effect.

val fire' : t -> fill list

Version of fire that is suitable to call from the iter callback of Fiber.run.

val fired : t -> bool

Return whether the given cancellation has been fired.

type 'a outcome =

| Cancelled of 'a
| Not_cancelled

val with_handler : 
  t ->
  (unit -> 'a fiber) ->
  on_cancel:(unit -> 'b fiber) ->
  ('a * 'b outcome) fiber

with_handler t ~on_cancel f runs f () with a cancellation handler. If t is fired during the execution of f, then on_cancel is called.

The aim of on_cancel is to somehow cut short the execution of f. A typical example is a function running an external command. on_cancel might send a KILL signal to the command to abort its execution.

If f () finished before t is fired, then on_cancel will never be invoked.