Event Module

(ev/call fn & args)

Call a function asynchronously. Returns a fiber that is scheduled to run the function.

(ev/cancel fiber err)

Cancel a suspended fiber in the event loop. Differs from cancel in that it returns the canceled fiber immediately

(ev/capacity channel)

Get the number of items a channel will store before blocking writers.

(ev/chan &opt capacity)

Create a new channel. capacity is the number of values to queue before blocking writers, defaults to 0 if not provided. Returns a new channel.

(ev/chunk stream n &opt buffer timeout)

Same as ev/read, but will not return early if less than n bytes are available. If an end of stream is reached, will also return early with the collected bytes.

(ev/close stream)

Close a stream. This should be the same as calling (:close stream) for all streams.

(ev/count channel)

Get the number of items currently waiting in a channel.

(ev/deadline sec &opt tocancel tocheck)

Set a deadline for a fiber `tocheck`. If `tocheck` is not finished after `sec` seconds, `tocancel` will be canceled as with `ev/cancel`. If `tocancel` and `tocheck` are not given, they default to `(fiber/root)` and `(fiber/current)` respectively. Returns `tocancel`.

(ev/full channel)

Check if a channel is full or not.

(ev/give channel value)

Write a value to a channel, suspending the current fiber if the channel is full.

(ev/go fiber &opt value)

Put a fiber on the event loop to be resumed later. Optionally pass a value to resume with, otherwise resumes with nil.

(ev/read stream n &opt buffer timeout)

Read up to n bytes into a buffer asynchronously from a stream. Optionally provide a buffer to write into as well as a timeout in seconds after which to cancel the operation and raise an error. Returns the buffer if the read was successful or nil if end-of-stream reached. Will raise an error if there are problems with the IO operation.

(ev/rselect & clauses)

Similar to ev/choice, but will try clauses in a random order for fairness.

(ev/select & clauses)

Block until the first of several channel operations occur. Returns a tuple of the form [:give chan] or [:take chan x], where a :give tuple is the result of a write and :take tuple is the result of a write. Each clause must be either a channel (for a channel take operation) or a tuple [channel x] for a channel give operation. Operations are tried in order, such that the first clauses will take precedence over later clauses.

(ev/sleep sec)

Suspend the current fiber for sec seconds without blocking the event loop.

(ev/spawn & body)

Run some code in a new fiber. This is shorthand for (ev/call (fn [] ;body)).

(ev/take channel)

Read from a channel, suspending the current fiber if no value is available.

(ev/with-deadline deadline & body)

Run a body of code with a deadline, such that if the code does not complete before
the deadline is up, it will be canceled.

(ev/write stream data &opt timeout)

Write data to a stream, suspending the current fiber until the write completes. Takes an optional timeout in seconds, after which will return nil. Returns nil, or raises an error if the write failed.