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refactor: 11-if/questions/5-short-if question #2

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Inanc Gumus
2018-11-12 01:06:26 +03:00
parent 230354a264
commit 418ff95fd3
1 changed files with 27 additions and 14 deletions
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41
11-if/questions/5-short-if.md
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@ -44,28 +44,41 @@ func main() {
> **3:** Yes. It shadows the main()'s done variable, and inside the if statement, it prints "true". Then, after the if statement ends, it prints the main()'s done variable which is "false". > **3:** Yes. It shadows the main()'s done variable, and inside the if statement, it prints "true". Then, after the if statement ends, it prints the main()'s done variable which is "false".
## How can you fix this code? ## There's a shadowing issue in this program. The program should print: 10, now it prints: 0.
**How can you fix this it?**
```go ```go
package main package main
import "fmt"
import (
"fmt"
"strconv"
)
func main() { func main() {
done := false var n int
if done := true; done {
fmt.Println(done) if n, err := strconv.Atoi("10"); err != nil {
} fmt.Printf("error: %s (n: %d)", err, n)
fmt.Println(done) return
}
fmt.Println(n)
} }
``` ```
1. Remove the first declaration (main()'s done)
2. Remove the declaration in the short-if (if's done) _See the code also in here: https://play.golang.org/p/fDrmcXWGnQB_
3. Change the done declaration of the main() to an assignment
4. Change the done declaration of the short-if to an assignment. And, after the if statement, assign false back to the done variable. *CORRECT* 1. Remove the first declaration (main()'s n variable).
2. Remove the declaration in the short-if (if's n).
3. Declare an error variable outside of the main.
4. Declare an error variable along with main's n variable, then change the short-if declaration to an assignment. *CORRECT*
> **1:** That will break the program. Because, the last line prints it. > **1:** That will break the program. Because, the last line prints it.
> >
> **2:** The program wants to use it to print true. > **2:** The program uses it to set the n.
> >
> **3:** There will be "undefined variable" error. > **3:** There will be "unused variable" error.
> **4:** Yes, that will solve the shadowing issue. Short-if will reuse the same done variable of the main(). And, after the short-if, done will be false because of the assignment, and it will print false. > **4:** Yes, that will solve the shadowing issue. Short-if will reuse the same 'n' variable (main()'s n). So, the converted number 'n' will be printed as: 10. See the solution here: https://play.golang.org/p/6jc-nZJNHYb