60 lines
887 B
Go
60 lines
887 B
Go
package main
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import (
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"fmt"
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"strings"
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"errors"
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"flag"
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"os"
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)
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//go:generate stringer -type=Movement
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type Movement int
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const (
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Unknown Movement = iota
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Forward
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Backward
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Left
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Right
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)
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func newMovement(movement string) (Movement) {
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switch strings.ToLower(movement) {
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case "forward":
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return Forward
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case "backward":
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return Backward
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case "left":
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return Left
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case "right":
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return Right
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default:
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return Unknown
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}
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}
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func main() {
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direction := flag.String("direction", "", "The direction to move.")
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flag.Parse()
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if err := run(*direction); err != nil {
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fmt.Printf("Error: %v.\n", err)
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os.Exit(1)
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}
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}
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func run(direction string) error {
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if len(direction) == 0 {
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return errors.New("direction is not set")
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}
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move := newMovement(direction)
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if move == Unknown {
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return errors.New("unknown direction")
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}
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fmt.Printf("I moved %s.\n", move)
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return nil
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}
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