45 lines
745 B
Go
45 lines
745 B
Go
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// For more tutorials: https://blog.learngoprogramming.com
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//
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// Copyright © 2018 Inanc Gumus
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// Learn Go Programming Course
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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//
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package main
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import (
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"fmt"
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"os"
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"strconv"
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)
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func main() {
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age := os.Args[1]
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// Atoi returns an int and an error value
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// So, you need to handle the errors
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n, err := strconv.Atoi(age)
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// handle the error immediately and quit
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// don't do anything else here
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if err != nil {
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fmt.Println("ERROR:", err)
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// quits/returns from the main function
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// so, the program ends
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return
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}
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// DO NOT DO THIS:
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// else {
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// happy path
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// }
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// DO THIS:
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// happy path (err is nil)
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fmt.Printf("SUCCESS: Converted %q to %d.\n", age, n)
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}
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