How to Resolve 'Imported and Not Used' and 'Undefined' Errors When Importing Types in Go?-Golang-php.cn

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How to Resolve 'Imported and Not Used' and 'Undefined' Errors When Importing Types in Go?

Mary-Kate Olsen

Nov 14, 2024 pm 01:35 PM

How to Resolve

Importing Packages and Types

When working on a project, it is often necessary to import packages and types from other modules or different parts of the same project. In Go, the import statement is used for this purpose.

Consider the following project structure:

src
├── config
    └── config.go
├── otherPackage
    └── otherFile.go
├── main.go

Suppose config.go contains a type named Config that you want to use in otherFile.go. After importing the config package, you might encounter the following issues:

"imported and not used"
"undefined: Config"

The reason for these errors is that the Config type is not explicitly referenced in otherFile.go. To resolve this, you need to qualify the type name with the package name. Since the config package is imported as "config," you would use config.Config to reference the type.

However, if you have a variable named "config" in otherFile.go, it will shadow the imported package, making config.Config ambiguous. To avoid this, rename your variable (e.g., to "cfg") or import the "config" package with an alias (e.g., "import c "full/import/path/of/config"" and then use "c.Config").

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