Why such strange things with scope?

Question

Node.js

Hello. The code is like this:

switch (data) {
        case 'buy': //как купить BTC
            const keys = message.buy.key[lng];
            keys.chat_id = msg.message.chat.id;
            keys.message_id = msg.message.message_id;
            bot.editMessageText(message.buy.text[lng], keys);
        break;

        case 'sell': //как продать BTC
            const keys = message.sell.key[lng];
            bot.editMessageText(message.sell.text[lng], keys);
        break;
    }

And in the console I see something unexpected:

Why does the compiler swear at the keys variable in the sell block? If I do not define it and try to pass it to bot.editMessageText, then the console says: keys is not defined.
Where is the mistake?
Z. Y. The keys variable does not occur elsewhere in the program. The message and lng variables are correct and available in both blocks

Answer 1

You have 2 times the declaration of const keys inside one block (the whole switch is one block)
, you can wrap each case in your own block, then it will work