用红色发出post请求时如何在头中使用变量

我正试图用红色语言发出一个post请求。

我必须传递带有授权的头,在发出请求并将其保存在变量中之前,我正在计算授权字符串的值 auth-string .

probe 打印 验证字符串 值罚款。

如果我在头部分中硬编码授权字符串,它是有效的,但是当我尝试使用变量时,程序就退出了。

此代码带有硬编码 Authorization: "Basic c29tZX... 作品:

username: "someusernamestring"
password: "somepasswordstring"

url: to url! rejoin ["https://example.com/" username "/Account.json"]

auth-string: rejoin ["Basic " enbase/base rejoin [username ":" password] 64]
probe auth-string

response: write url [
        post [
        Content-Type: "application/x-www-form-urlencoded"
        Authorization: "Basic c29tZXVzZXJuYW1lc3RyaW5nOnNvbWVwYXNzd29yZHN0cmluZw=="
    ]
    {}    
]

print response

但是,这段代码, Authorization: auth-string 不工作,程序退出,没有错误,我可以看到。

username: "someusernamestring"
password: "somepasswordstring"

url: to url! rejoin ["https://example.com/" username "/Account.json"]

auth-string: rejoin ["Basic " enbase/base rejoin [username ":" password] 64]
probe auth-string

response: write url [
        post [
        Content-Type: "application/x-www-form-urlencoded"
        Authorization: auth-string
    ]
    {}    
]

print response

如何在headers部分使用变量?