ReasonML javascript 记录字段
ReasonML javascript record field
假设我有以下 Bucklescript 类型:
type amqp;
[@bs.val] external amqpLib: amqp = "Amqp";
[@bs.module] external amqplib : amqp = "";
class type amqpConnectionT =
[@bs]
{
pub createChannel: unit => unit;
pub close: unit => unit
};
type amqpConnection = Js.t(amqpConnectionT);
let make = () => amqplib;
[@bs.send] external connect : (amqp, string) => Js.Promise.t(amqpConnection) = "";
let connectAmqp = (input: string, amqpClient: amqp) : Js.Promise.t(amqpConnection) => connect(amqpClient, input);
let makeConnection = (input) => make() |> connectAmqp(input, _);
然后是下面的代码:
let start = () =>
Amqp.makeConnection("amqp://localhost")
|> Js.Promise.then_(connection => {
Js.log(connection);
connection.createChannel();
Js.Promise.resolve(connection);
});
start();
这失败了:
The record field createChannel can't be found.
为什么?我的类型注释怎么不正确?
在 ReasonML 中公开这样的成员方法的正确方法是什么?
尝试 connection##createChannel()
如果它来自 JS。
当您使用 . 访问器时,编译器认为连接是一条记录
假设我有以下 Bucklescript 类型:
type amqp;
[@bs.val] external amqpLib: amqp = "Amqp";
[@bs.module] external amqplib : amqp = "";
class type amqpConnectionT =
[@bs]
{
pub createChannel: unit => unit;
pub close: unit => unit
};
type amqpConnection = Js.t(amqpConnectionT);
let make = () => amqplib;
[@bs.send] external connect : (amqp, string) => Js.Promise.t(amqpConnection) = "";
let connectAmqp = (input: string, amqpClient: amqp) : Js.Promise.t(amqpConnection) => connect(amqpClient, input);
let makeConnection = (input) => make() |> connectAmqp(input, _);
然后是下面的代码:
let start = () =>
Amqp.makeConnection("amqp://localhost")
|> Js.Promise.then_(connection => {
Js.log(connection);
connection.createChannel();
Js.Promise.resolve(connection);
});
start();
这失败了:
The record field createChannel can't be found.
为什么?我的类型注释怎么不正确?
在 ReasonML 中公开这样的成员方法的正确方法是什么?
尝试 connection##createChannel()
如果它来自 JS。
当您使用 . 访问器时,编译器认为连接是一条记录