函数不适用于 if else 语句

Question

我正试图用Go作为教程构建一个基本的缓存系统。

由于某种原因，当我运行这个时，if-else语句会导致一个错误。

package datasource
import (
"fmt"
"github.com/patrickmn/go-cache"
"time"
)
type DataSource interface {
Value(key string) (interface{}, error)
}
// DataSourceStr type, implements the DataSource interface
type DataSourceStr struct {
data map[string]string
}

var cache = cache.New(5*time.Minute, 5*time.Minute)

func (n *DataSourceStr) Value(key string) (interface{}, error) {
/* 
1. Compute a cache key
2. Search cache key
3. If hit return value
4. If miss, do datasource
5. Cache and return slow thing.
*/

cached, found := cache.Value(key)
if found {
return cached, nil
}
else if _, ok := n.data[key]; ok 
{
//measure how often a key gets called.
cache.Set(key, n.data[key], cache.DefaultExpiration)
return n.data[key], nil
} else {
return nil, fmt.Errorf("key not found %v", ok)
}
}


func getFromDS(datasource DataSource, key string) (string, error) {

v, err := datasource.Value(key)

//create a map that decays based on time.
if err != nil {
return "", nil
}
return fmt.Sprint(v), nil
}

我做错了什么？我正在尝试输入一个键，然后从缓存或数据库返回值。不确定我在语法上做错了什么！

Answer 1

go条件语句遵循以下语法

if something{
......
} else if something{
......
} else{
......
}

的详细答案