ask whether overwrite the file

util.go

@@ -16,6 +16,7 @@ package main
 
 import (
 	"fmt"
+	"log"
 	"os"
 	"path/filepath"
 	"runtime"
@@ -170,3 +171,35 @@ func GetGOPATHs() []string {
 	}
 	return paths
 }
+
+// askForConfirmation uses Scanln to parse user input. A user must type in "yes" or "no" and
+// then press enter. It has fuzzy matching, so "y", "Y", "yes", "YES", and "Yes" all count as
+// confirmations. If the input is not recognized, it will ask again. The function does not return
+// until it gets a valid response from the user. Typically, you should use fmt to print out a question
+// before calling askForConfirmation. E.g. fmt.Println("WARNING: Are you sure? (yes/no)")
+func askForConfirmation() bool {
+	var response string
+	_, err := fmt.Scanln(&response)
+	if err != nil {
+		log.Fatal(err)
+	}
+	okayResponses := []string{"y", "Y", "yes", "Yes", "YES"}
+	nokayResponses := []string{"n", "N", "no", "No", "NO"}
+	if containsString(okayResponses, response) {
+		return true
+	} else if containsString(nokayResponses, response) {
+		return false
+	} else {
+		fmt.Println("Please type yes or no and then press enter:")
+		return askForConfirmation()
+	}
+}
+
+func containsString(slice []string, element string) bool {
+	for _, elem := range slice {
+		if elem == element {
+			return true
+		}
+	}
+	return false
+}