Bug spot game

Today, we are going to play a game. You have to look at some Go code, and spot the bug.

• Don’t run the code; it’s a mental game.
• Double quotes are stylised in Medium, so that’s never the answer.
• Answers are listed at the bottom in Base64 (see how Drew LeSueur dealt with this)

NUMBER ONE: Errors in errors

package main

import (
  “errors”
  “fmt”
)

func main() {
  err := errors.New(“emit macho dwarf: elf header corrupted”)
  if err != nil {
    fmt.Printf(err)
  }
}

---

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NUMBER TWO: Wait a minute

select {
case m := <-c:
    handle(m)
case time.After(5 * time.Minute):
  fmt.Println("timed out")
}

---

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NUMBER THREE: Pretty unique

// UniqueStrings gets an array containing unique stirngs.
func UniqueStrings(s ...string) []string {
  var strs []string
loop:
  for _, str := range s {
    for _, foundStr := range strs {
      if str == foundStr {
        continue
      }
    }
    strs = append(strs, str)
  }
  return strs
}

---

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NUMBER FOUR: What’s Jason pointing at?

package main

import (
 “bytes”
 “encoding/json”
 “log”
 “os”
)

func main() {

  type Road struct {
    Name string
    Number int
  }
  roads := []Road{
    {“Diamond Fork”, 29},
    {“Sheep Creek”, 51},
  }

  b, err := json.Marshal(roads)
  if err != nil {
    log.Fatal(err)
  }

  var out bytes.Buffer
  json.Indent(out, b, “=”, “\t”)
  out.WriteTo(os.Stdout)

}

---

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NUMBER FIVE: Scanning

package main

import (
  “bufio”
  “fmt”
  “os”
)

func main() {
  scanner := bufio.NewScanner(os.Stdin)
  for scanner.Scan() {
    fmt.Println(scanner.Text())
  }
  if err = scanner.Err(); err != nil {
    fmt.Fprintln(os.Stderr, “reading standard input:”, err)
  }
}

---

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HARD bonus question

Stretch goal…

NUMBER SEVEN: Trick question

package main

import “fmt”

func main() {

  var card = struct{
    Suit string
    Value int
  }{“Hearts”,5}

  fmt.Println(“The card is:”, *(&card))

}

---

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