Resulto

A Rust-inspired Result type for Go, enabling elegant error handling with generics.

Features

• Generic Result type supporting any value and error types
• Chainable operations for cleaner error handling
• Panic-free error propagation
• Fully tested and production-ready

Installation

go get github.com/osesantos/resulto

Usage

Basic Usage

package main

import (
    "errors"
    "fmt"
    "github.com/osesantos/resulto"
)

func divide(a, b int) resulto.Result[int] {
    if b == 0 {
        return resulto.Failure[int](errors.New("division by zero"))
    }
    return resulto.Success(a / b)
}

func main() {
    // Successful result
    result1 := divide(10, 2)
    if result1.IsOk() {
        fmt.Printf("Result: %d\n", result1.Unwrap())
    }
    
    // Failed result with safe unwrap
    result2 := divide(5, 0)
    value := result2.UnwrapOr(0)
    fmt.Printf("Safe value: %d\n", value)
}

Advanced Usage

package main

import (
    "errors"
    "fmt"
    "github.com/osesantos/resulto"
    "strconv"
)

func parseAndDouble(input string) resulto.Result[int] {
    return parseString(input).Map(func(n int) int {
        return n * 2
    })
}

func parseString(input string) resulto.Result[int] {
    n, err := strconv.Atoi(input)
    if err != nil {
        return resulto.Failure[int](err)
    }
    return resulto.Success(n)
}

func main() {
    // Chaining operations
    parseAndDouble("5").Match(
        func(n int) { fmt.Printf("Doubled: %d\n", n) },
        func(err error) { fmt.Printf("Error: %s\n", err.Error()) },
    )
    
    // Error handling
    parseAndDouble("invalid").Match(
        func(n int) { fmt.Printf("Doubled: %d\n", n) },
        func(err error) { fmt.Printf("Error: %s\n", err.Error()) },
    )
}

API Reference

Creating Results

• Success[T](value T) Result[T]: Create a successful result
• Failure[T](err error) Result[T]: Create a failed result

Methods

• IsOk() bool: Check if result is successful
• Unwrap() T: Get value or panic if error
• UnwrapOr(def T) T: Get value or default if error
• UnwrapErr() error: Get error or panic if successful

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details.