45 lines
		
	
	
		
			745 B
		
	
	
	
		
			Go
		
	
	
	
	
	
			
		
		
	
	
			45 lines
		
	
	
		
			745 B
		
	
	
	
		
			Go
		
	
	
	
	
	
| // 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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| 
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| package main
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| 
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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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| 
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| func main() {
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| 	age := os.Args[1]
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| 
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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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| 
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| 	n, err := strconv.Atoi(age)
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| 
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| 	// handle the error immediately and quit
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| 	// don't do anything else here
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| 
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| 	if err != nil {
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| 		fmt.Println("ERROR:", err)
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| 
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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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| 
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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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| 
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| 	// DO THIS:
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| 
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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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