Callback Library

A lightweight Odin library for creating stateful callbacks.
This library avoids heap allocations by default, relying solely on stack memory. It also supports optional cleanup functions for managing resources. Licensed under the MIT License.

Features

Stateful callbacks: Pair state with a callback function.
Memory-efficient: No heap allocations.
Optional cleanup: Support for resource cleanup when needed.

Installation

Copy the callback package into your Odin project. Import it with:

import "path/to/callback"

API Overview

Types

Callback(TParam, TReturn): A structure that holds a callback, its state, and an optional cleanup function.

Functions

make_without_cleanup(capture: rawptr, callback: proc(rawptr, P) -> R)
Creates a callback without a cleanup function.
make_with_cleanup(capture: rawptr, callback: proc(rawptr, P) -> R, free: proc(rawptr))
Creates a callback with a cleanup function for resource management.
make
Procedure union for creating a callback with or without cleanup.
exec(c: Callback(P, R), param: P) -> R
Executes the callback and returns the result.
free(c: Callback(P, R))
Invokes the cleanup function if it is set.

Usage Example

package main

import "callback"

make_adder :: proc(base: int) -> cb.Callback(int, int) {
    return cb.make(
        capture = new_clone(base),
        callback = proc(capture: ^int, param: int) -> int {
            capture^ += param
            return capture^
        },
        free = proc(capture: rawptr) {
            free(cast(^int)capture)
        },
    )
}

main :: proc() {
    adder := make_adder(10)
    defer cb.free(adder) // Cleanup

    cb.exec(adder, 5) // 15
    cb.exec(adder, 6) // 21
    cb.exec(adder, 7) // 28
}

License

This library is licensed under the MIT License.

odin-callback