2021-01-18_index_part3d.js

if (message.content.startsWith(`${prefix}whois`)) {
    // if the message contains any mentions, pick the first as the target
    if (message.mentions.users.size) {
        const taggedUser = message.mentions.users.first()
        message.channel.send(
            `User Info: ${
                taggedUser.username
            } (account created: ${taggedUser.createdAt.toUTCString()})`,
        )
    } else {
        // default to sender if no user is mentioned
        const { author } = message
        message.reply(
            `User Self Info: ${
                author.username
            } (account created: ${author.createdAt.toUTCString()})`,
        )
    }
}