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package csvutil_test
import (
"encoding/csv"
"errors"
"fmt"
"strconv"
"strings"
"time"
"unicode"
"github.com/jszwec/csvutil"
)
type IntStruct struct {
Value int
}
func (i *IntStruct) Scan(state fmt.ScanState, verb rune) error {
switch verb {
case 'd', 'v':
default:
return errors.New("unsupported verb")
}
t, err := state.Token(false, unicode.IsDigit)
if err != nil {
return err
}
n, err := strconv.Atoi(string(t))
if err != nil {
return err
}
*i = IntStruct{Value: n}
return nil
}
func ExampleDecoder_Register() {
type Foo struct {
Time time.Time `csv:"time"`
Hex int `csv:"hex"`
PtrHex *int `csv:"ptr_hex"`
IntStruct IntStruct `csv:"int_struct"`
}
unmarshalInt := func(data []byte, n *int) error {
v, err := strconv.ParseInt(string(data), 16, 64)
if err != nil {
return err
}
*n = int(v)
return nil
}
unmarshalTime := func(data []byte, t *time.Time) error {
tt, err := time.Parse(time.Kitchen, string(data))
if err != nil {
return err
}
*t = tt
return nil
}
unmarshalScanner := func(data []byte, s fmt.Scanner) error {
_, err := fmt.Sscan(string(data), s)
return err
}
const data = `time,hex,ptr_hex,int_struct
12:00PM,f,a,34`
r := csv.NewReader(strings.NewReader(data))
dec, err := csvutil.NewDecoder(r)
if err != nil {
panic(err)
}
dec.Register(unmarshalInt)
dec.Register(unmarshalTime)
dec.Register(unmarshalScanner)
var foos []Foo
if err := dec.Decode(&foos); err != nil {
fmt.Println("error:", err)
}
fmt.Printf("%s,%d,%d,%+v",
foos[0].Time.Format(time.Kitchen),
foos[0].Hex,
*foos[0].PtrHex,
foos[0].IntStruct,
)
// Output:
// 12:00PM,15,10,{Value:34}
}
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