Overview

Package name and the name of the directory containing that package don’t necessarily have to be the same. Then what does the import path of a package specify? For example in case we any package, then the import path might like as below

import "xyz.com/abc/sample"

Above statement essentially means that import package present at directory “sample”. It doesn’t mean import package sample. To validate that let’s see an example.

Example

Let’s first create a directory named learn and then create a module with import path as “sample.com/learn”.

go mod create sample.com/learn

Let’s create a directory named math inside the learn directory. Create a file math.go inside the math directory with below contents

learn/math/math.go

package mathematics

func Add(a, b int) int {
    return a + b
}

Notice the package declaration above

package mathematics

The package name is mathematics but the name of the directory containing that package is math.

Now let’s use the mathematics package in the main.go file.

learn/main.go

package main

import (
    "fmt"
    "sample.com/learn/math"
)

func main() {
    fmt.Println(mathematics.Add(2, 1))
}

In main.go above, see how we import the package.

"sample.com/learn/math"

Above statement essentially means that import package present at directory “math”. It doesn’t mean import package math.

See how in the main function we are using the package.

fmt.Println(mathematics.Add(2, 1))

This is what we meant when we said  import means to import package present at that directory location.

If you run this program, output will be correct.

3

This shows that name of the package doesn’t necessarily needs to be same as the name of the directory containing the package. Another convenient way is to use package aliasing in such case like below

import (
    "fmt"
    mathematics "sample.com/learn/math"
)