Listener Class

A `Listener` object represents an event handler within a [`Router`]. Each listener pairs an `event` type (e.g., `"start"`, `"error"`, `"finish"`) with a function `FUN` to execute when that event is triggered.

Format

An [`R6::R6Class`] generator for `Listener` objects.

See also

[Router], [Error]

Public fields

FUN

Handler function to execute when `event` is triggered.

event

Event name (e.g., `"start"`, `"error"`, `"finish"`).

Methods

Public methods

• Listener$new()

• Listener$clone()

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Method new()

Construct a listener by setting its `event` and handler `FUN`.

Usage

Listener$new(event, FUN, ...)

Arguments

event

Event name string.

FUN

Function to call when the event occurs.

...

Ignored; accepted for flexibility.

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Method clone()

The objects of this class are cloneable with this method.

Usage

Listener$clone(deep = FALSE)

Arguments

deep

Whether to make a deep clone.