Golang Try Catch Finally 🔥

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🚧 WARNING: DEMONSTRATION PURPOSES ONLY 🚧

Attention, visitors and developers! This repository is solely intended for demonstrating the remarkable features and capabilities of the Go programming language. It is NOT suitable for utilization in any production or real-world project.
You can find detailed information on how to handle errors in Go in the article titled "Error Handling and Go." Access the article directly using the following link:
🔗 Error Handling and Go Documentation

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Golang Try Catch Finally is a simple demonstration of how to implement the try-catch-finally functionality in Go.
The key features of go-try:

• try - the try block, which can execute any code that may cause an error without the need of handling errors in idiomatic Go style.
• catch - the catch block, which can handle errors that occur in the try block.
• finally - the finally block, which is executed after the try block regardless of whether an error occurred or not.

Getting Started

With Go module support, simply add the following import

import "github.com/okhomin/go-try"

to your code, and then go [build|run|test] will automatically fetch the necessary dependencies.
Otherwise, run the following Go command to install the go-try package:

go get github.com/okhomin/go-try

Usage

The following code snippet demonstrates how to use the go-try package:

package main

import (
	. "github.com/okhomin/go-try"
	"fmt"
	"io"
	"os"
)

func main() {
	var file *os.File
	var data []byte

	Try(func() {
		file = Try1(os.Open("test.txt"))
		data = Try1(io.ReadAll(file))
	}).Finally(func() {
		fmt.Println("This code block will be executed no matter what")
	}).Catch(CatchMap{
		os.ErrNotExist: func(err error) {
			fmt.Printf("File does not exist: %v\n", err)
		},
		AnyError: func(err error) {
			fmt.Println("This code block will be executed if any error occurs except os.ErrNotExist")
		},
	})

	fmt.Println(string(data))
}

Since the module is imported with the dot prefix, the Try, Catch, and Finally functions can be called directly without the need to specify the package name.

Try

The Try function is used to execute the code that may cause an error.

Try(func() {
    file = Try1(os.Open("test.txt"))
    data = Try1(io.ReadAll(file))
})

Try0, Try1, Try2, ..., Try10

All the functions that can return an error must be wrapped with the Try function.
In the example above, the Try1 function is used to wrap the os.Open function, which returns a file and an error.

file = Try1(os.Open("test.txt"))

After using the Try1 function, the file variable will contain the file if no error occurred. Otherwise, the file variable will be nil and the error will be handled in the Catch block.

data = Try1(io.ReadAll(file))

The Try1 function can be used to wrap the io.ReadAll function, which returns a byte slice and an error.

CatchMap

The CatchMap type is a map of error types and functions that handle errors of the corresponding types.

CatchMap{
    os.ErrNotExist: func(err error) {
        fmt.Printf("File does not exist: %v\n", err)
    },
    AnyError: func(err error) {
        fmt.Println("This code block will be executed if any error occurs except os.ErrNotExist")
    },
}

AnyError is a special error type that is used to handle any error that occurs in the Try block and is not handled by any other error type.

Finally

The Finally function is used to execute the code that must be executed after the Try block regardless of whether an error occurred or not.

Finally(func() {
    fmt.Println("This code block will be executed no matter what")
})

The Finally block can be omitted if it is not needed.

License

Distributed under the MIT License. See LICENSE for more information.