http://play.golang.org/p/kwc32A5mJf

csv.go

package main

import (
	"encoding/csv"
	"fmt"
	"io"
	"reflect"
	"strconv"
	"strings"
)

type Test struct {
	Name    string
	Surname string
	Age     int
}

func Unmarshal(reader *csv.Reader, v interface{}) error {
	record, err := reader.Read()
	if err != nil {
		return err
	}
	s := reflect.ValueOf(v).Elem()
	if s.NumField() != len(record) {
		return &FieldMismatch{s.NumField(), len(record)}
	}
	for i := 0; i < s.NumField(); i++ {
		f := s.Field(i)
		switch f.Type().String() {
		case "string":
			f.SetString(record[i])
		case "int":
			ival, err := strconv.ParseInt(record[i], 10, 0)
			if err != nil {
				return err
			}
			f.SetInt(ival)
		default:
			return &UnsupportedType{f.Type().String()}
		}
	}
	return nil
}

func main() {
	var source = "John;Smith;42\nPiter;Abel;50"
	var reader = csv.NewReader(strings.NewReader(source))
	reader.Comma = ';'
	var test Test
	for {
		err := Unmarshal(reader, &test)
		if err == io.EOF {
			break
		}
		if err != nil {
			panic(err)
		}
		fmt.Printf("%s %s has age of %d\n", test.Name, test.Surname, test.Age)
	}
}

type FieldMismatch struct {
	expected, found int
}

func (e *FieldMismatch) Error() string {
	return "CSV line fields mismatch. Expected " + strconv.Itoa(e.expected) + " found " + strconv.Itoa(e.found)
}

type UnsupportedType struct {
	Type string
}

func (e *UnsupportedType) Error() string {
	return "Unsupported type: " + e.Type
}