Example
You can import a single package with the statement:
import "path/to/package"
or group multiple imports together:
import (
"path/to/package1"
"path/to/package2"
)
This will look in the corresponding import paths inside of the $GOPATH for .go files and lets you access exported names through packagename.AnyExportedName.
You can also access local packages inside of the current folder by prefacing packages with ./. In a project with a structure like this:
project
├── src
│ ├── package1
│ │ └── file1.go
│ └── package2
│ └── file2.go
└── main.go
You could call this in main.go in order to import the code in file1.go and file2.go:
import (
"./src/package1"
"./src/package2"
)
Since package-names can collide in different libraries you may want to alias one package to a new name. You can do this by prefixing your import-statement with the name you want to use.
import (
"fmt" //fmt from the standardlibrary
tfmt "some/thirdparty/fmt" //fmt from some other library
)
This allows you to access the former fmt package using fmt.* and the latter fmt package using tfmt.*.
You can also import the package into the own namespace, so that you can refer to the exported names without the package. prefix using a single dot as alias:
import (
. "fmt"
)
Above example imports fmt into the global namespace and lets you call, for example, Printf directly: Playground
If you import a package but don't use any of it's exported names, the Go compiler will print an error-message. To circumvent this, you can set the alias to the underscore:
import (
_ "fmt"
)
This can be useful if you don't access this package directly but need it's init functions to run.
Note:
As the package names are based on the folder structure, any changes in the folder names & import references (including case sensitivity) will cause a compile time error "case-insensitive import collision" in Linux & OS-X, which is difficult to trace and fix (the error message is kinda cryptic for mere mortals as it tries to convey the opposite - that, the comparison failed due to case sensitivity).
ex: "path/to/Package1" vs "path/to/package1"
Live example: https://github.com/akamai-open/AkamaiOPEN-edgegrid-golang/issues/2
