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Golang program to demonstrate the os.Expand() function

Here, we are going to demonstrate the os.Expand() function in Golang (Go Language).
Submitted by Nidhi, on April 20, 2021 [Last updated : March 05, 2023]

os.Expand() function in Golang

Problem Solution:

In this program, we will use os.Expand() function to expand or format a specified string with specified function and print the result on the console screen.

Program/Source Code:

The source code to demonstrate os.Expand() function is given below. The given program is compiled and executed on the ubuntu 18.04 operating system successfully.

Golang code to demonstrate the example of os.Expand() function

// Golang program to demonstrate the
// os.Expand() function

package main

import "fmt"
import "os"

func GetVal(val string) string {
	switch val {
	case "Name":
		return "Morrish"
	case "City":
		return "New York"
	default:
		return "<Empty>"
	}
}

func main() {
	str := "My name is $Name and live in $City."

	//Format the specified string using os.Expand
	strResult := os.Expand(str, GetVal)

	fmt.Println(strResult)
}

Output:

My name is Morrish and live in New York.

Explanation:

In the above program, we declare the package main. The main package is used to tell the Go language compiler that the package must be compiled and produced the executable file. Here, we imported the "fmt" package to use the Printf() function and we also imported the "os" package to use the Expand() function.

func GetVal(val string) string {
	switch val {
	case "Name":
		return "Morrish"
	case "City":
		return "New York"
	default:
		return "<Empty>"
	}
}

In the above code, we created a function GetVal() that returns the value based on a specified parameter.

In the main() function, we formatted a string using os.Expand() function and print the result on the console screen.

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