Node.js Discord bot throwing undefined variable error when checking message content

[Emma_Fluffy]

I’m working on a Discord bot that automatically removes messages after a delay, but I want certain messages to be exempt from deletion. Specifically, I need messages containing *SAVE to not get deleted.

Here’s my current approach:

const Discord = require('discord.js');
const client = new Discord.Client();

client.on('message', msg => {
  const text = msg.content.toLowerCase();
  if(text.includes('*save')) {
    if (exemptFlag === null) {
      setTimeout(() => {
        client.deleteMessage(msg);
      }, 180000);
    }
  }
});

This is my basic message deletion handler:

client.on('message', msg => {
  setTimeout(() => {
    client.deleteMessage(msg);
  }, 180000);
});

The problem is I keep getting a ReferenceError saying exemptFlag is not defined whenever someone types *SAVE in the chat. How can I properly implement this conditional logic to prevent deletion of specific messages?

[JollyMusic3]

You’re getting that error because exemptFlag isn’t declared anywhere. Your code’s way more complicated than it needs to be. Just merge both handlers and use early returns:

client.on('message', msg => {
  const text = msg.content.toLowerCase();
  
  // Skip deletion if message contains *save
  if(text.includes('*save')) {
    return;
  }
  
  // Delete all other messages after 3 minutes
  setTimeout(() => {
    msg.delete();
  }, 180000);
});

BTW, client.deleteMessage() is deprecated - use msg.delete() instead. This fixes your undefined variable problem and keeps things simple.

[alexr1990]

you forgot to declare the exemptFlag var. just ditch that whole if statement - if the message has ‘*save’ then don’t set any timeout. restructure it so ‘*save’ msgs skip deletion completely instead of checking undefined vars.

[joec]

The problem is you’re trying to use exemptFlag without declaring it first. But your logic’s backwards anyway - you’re setting a deletion timeout inside the condition that’s supposed to prevent deletion. You want to only set the timeout when the message doesn’t contain ‘*save’. Here’s a cleaner approach:

client.on('message', msg => {
  const text = msg.content.toLowerCase();
  
  if (!text.includes('*save')) {
    setTimeout(() => {
      msg.delete().catch(console.error);
    }, 180000);
  }
});

This way messages with ‘*save’ never get a deletion timer, while everything else gets deleted after 3 minutes. Added error handling since messages might already be deleted by users or other bots.