打字稿问题 - “类型‘字符串’不能用作索引”

Question

所以我正在开发一个不和谐的机器人。现在我试图找到一种方法来实现它，以便我可以将别名传递给命令。我几乎拥有它，但现在我遇到了数组需要参数的地方，现在我卡住了。

import { CommandResponse } from "./commands/command";
import { commands } from "./commands";

import { DiscordBot } from "../server";

import * as Discord from "discord.js";

interface CommandMap {
    [command: string]: Function;
}

/**
 * Handle command interactions
 *
 * @export
 * @class Command
 */
export class Command {
    private commands: CommandMap = {};

    /**
     * Creates an instance of Command.
     * @param {DiscordBot} bot
     * @memberof Command
     */
    constructor(private bot: DiscordBot) {
        commands.forEach(command => {
            this.commands[command.commandName, command.commandAlias] = command.buildResponse;
        })
        console.log(commands);
    }

    /**
     * Run a command by name
     *
     * @param {string} command the command to run 
     * @param {Discord.Message} message send the raw command message
     * @returns {Promise<CommandResponse>} the command's response
     * @memberof Command
     */
    public async runCommand(command: string, message: Discord.Message): Promise<CommandResponse> {
        if (this.commands[command] === undefined) return null;
        return this.commands[command](message.author.id, message, this.bot);
    }
}

我最初的问题是 command.commandAlias[] 参数不能用作索引。这里也是对命令结构本身的引用：

export interface CommandResponse {
    response: any;
    channelId: number;
    mention: boolean;
}

export interface ICommand {
    commandName: string;
    commandAlias: string[];
    buildResponse(user: number, message: any, bot: DiscordBot): Promise<CommandResponse>;
}