Troubleshooting TypeScript Discord.js Null Checking Issue

I've been facing an obstacle while trying to make my Discord bot work in TypeScript. Every time I attempt msg.reply(string), I get the error message "Cannot invoke an object which is possibly 'null'." despite having just checked if it is null. Below is my current code:

import Discord = require("discord.js");

const client: Discord.Client = new Discord.Client();

client.on("ready", () => {
    console.log(`connected as ${client.user?.tag}`);
});

client.on("message", msg => {
    if (msg == null){
        return;
    }

    msg.reply("hi");
});

Although disabling strict null checking can solve this issue, I prefer to keep it enabled.

I would greatly appreciate any assistance, thank you!

edit:

This is the error that the VS Code compiler displays:

app.ts:14:5 - error TS2721: Cannot invoke an object which is possibly 'null'.

14     msg.reply("hi");
       ~~~~~~~~~


Found 1 error.

The terminal process terminated with exit code: 2

Answer №1

Place the code utilizing msg inside the provided conditional block, like so:

client.on("message", msg => {
    if (msg){
        msg.reply("hello");
    }
});

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