无法在字符串映射内使用字符串的基础类型：“不能在映射索引中使用<xxx>（类型<yyy>）作为字符串类型”

I have underlying type of string: type Capability string.

I wanted to use it as a string inside map of strings but I am getting an error:

cannot use cap (type Capability) as type string in map index

This is my code:

package main

import (
    "fmt"
)


type Capability string
var caps_list = map[string]int {
    "HOME" : 1,
}

func main() {

    var cap Capability // string
    cap = "HOME"
    fmt.Print(string(caps_list[cap]))
}  

Why it doesn't accept it ? it is a string after all.

You can try my code here:
https://play.golang.org/p/r-h9Hu8_eoM

</div>

Just need to change to use string on the cap:

fmt.Print(string(caps_list[string(cap)]))  

No it is not a string. It is a type, wich base type is a string.

So the exact type is important. You can also not add celcius to fahrenheit degrees, even if both types would have integer base types.