// parse.go package parse import ( "fmt" "strconv" "strings" ) // A ParseError indicates an error in converting a word into an integer. type ParseError struct { Index int // The index into the space-separated list of words. Word string // The word that generated the parse error. Err error // The raw error that precipitated this error, if any. } // String returns a human-readable error message. func (e *ParseError) String() string { return fmt.Sprintf("pkg parse: error parsing %q as int", e.Word) } // Parse parses the space-separated words in in put as integers. func Parse(input string) (numbers []int, err error) { defer func() { if r := recover(); r != nil { var ok bool err, ok = r.(error) if !ok { err = fmt.Errorf("pkg: %v", r) } } }() fields := strings.Fields(input) numbers = fields2numbers(fields) return } func fields2numbers(fields []string) (numbers []int) { if len(fields) == 0 { panic("no words to parse") } for idx, field := range fields { num, err := strconv.Atoi(field) if err != nil { panic(&ParseError{idx, field, err}) } numbers = append(numbers, num) } return }