# Error Handling In Go, Part II

DevFeed: [Error Handling In Go, Part II](<https://devfeed.tech/articles/error-handling-in-go-part-ii-22107.md>)

Original publisher: [Read original article](<https://www.ardanlabs.com/blog/2014/11/error-handling-in-go-part-ii.html>)

Published: 2014-11-10T00:00:00Z

Content type: tutorial

Language: en

Sources: [William Kennedy](<https://devfeed.tech/sources/william-kennedy.md>)

Topics: [Error Handling](<https://devfeed.tech/topics/error-handling.md>), [Go Language](<https://devfeed.tech/topics/go-language.md>)

Tags: [ardan-labs](<https://devfeed.tech/tags/ardan-labs.md>), [blog](<https://devfeed.tech/tags/blog.md>), [error-handling](<https://devfeed.tech/tags/error-handling.md>), [error-interface](<https://devfeed.tech/tags/error-interface.md>), [errors](<https://devfeed.tech/tags/errors.md>), [go](<https://devfeed.tech/tags/go.md>), [go-programming](<https://devfeed.tech/tags/go-programming.md>), [golang](<https://devfeed.tech/tags/golang.md>), [how-to](<https://devfeed.tech/tags/how-to.md>), [interface](<https://devfeed.tech/tags/interface.md>), [library](<https://devfeed.tech/tags/library.md>), [packages](<https://devfeed.tech/tags/packages.md>), [pointers](<https://devfeed.tech/tags/pointers.md>), [programming](<https://devfeed.tech/tags/programming.md>), [standard](<https://devfeed.tech/tags/standard.md>), [standard-library](<https://devfeed.tech/tags/standard-library.md>), [types](<https://devfeed.tech/tags/types.md>)

## AI overview

This tutorial explains when custom error types in Go are useful, especially when callers need additional context for error-handling decisions. It examines the standard library's net package and its OpError type, then discusses identifying concrete values stored in error interfaces.

## Source excerpt

Introduction In part I of this post, we learned about the error interface and how the standard library provides support for creating error interface values via the errors package. We also learned how to work with error interface values and use them to identify when an error has occured. Finally, we saw how some packages in the standard library export error interface variables to help us identify specific errors.