Fiber Module

(fiber/can-resume? fiber)

Check if a fiber is finished and cannot be resumed.

(fiber/current)

Returns the currently running fiber.

(fiber/getenv fiber)

Gets the environment for a fiber. Returns nil if no such table is set yet.

(fiber/last-value fiber)

Get the last value returned or signaled from the fiber.

(fiber/maxstack fib)

Gets the maximum stack size in janet values allowed for a fiber. While memory for the fiber's stack is not allocated up front, the fiber will not allocated more than this amount and will throw a stack-overflow error if more memory is needed. 

(fiber/new func &opt sigmask env)

Create a new fiber with function body func. Can optionally take a set of signals `sigmask` to capture from child fibers, and an environment table `env`. The mask is specified as a keyword where each character is used to indicate a signal to block. If the ev module is enabled, and this fiber is used as an argument to `ev/go`, these "blocked" signals will result in messages being sent to the supervisor channel. The default sigmask is :y. For example,

 (fiber/new myfun :e123)

blocks error signals and user signals 1, 2 and 3. The signals are as follows:

* :a - block all signals
* :d - block debug signals
* :e - block error signals
* :t - block termination signals: error + user[0-4]
* :u - block user signals
* :y - block yield signals
* :w - block await signals (user9)
* :r - block interrupt signals (user8)
* :0-9 - block a specific user signal

The sigmask argument also can take environment flags. If any mutually exclusive flags are present, the last flag takes precedence.

* :i - inherit the environment from the current fiber
* :p - the environment table's prototype is the current environment table

(fiber/root)

Returns the current root fiber. The root fiber is the oldest ancestor that does not have a parent.

(fiber/setenv fiber table)

Sets the environment table for a fiber. Set to nil to remove the current environment.

(fiber/setmaxstack fib maxstack)

Sets the maximum stack size in janet values for a fiber. By default, the maximum stack size is usually 8192.

(fiber/status fib)

Get the status of a fiber. The status will be one of:

* :dead - the fiber has finished
* :error - the fiber has errored out
* :debug - the fiber is suspended in debug mode
* :pending - the fiber has been yielded
* :user(0-7) - the fiber is suspended by a user signal
* :interrupted - the fiber was interrupted
* :suspended - the fiber is waiting to be resumed by the scheduler
* :alive - the fiber is currently running and cannot be resumed
* :new - the fiber has just been created and not yet run