TypeScript Dilemma: Redundant Function Declaration and Block-Scoped Variable Cannot be Redefined

Trying to get the hang of 'TypeScript in 5 Minutes' but running into some issues:

https://www.typescriptlang.org/docs/handbook/typescript-in-5-minutes.html

Despite my efforts, I keep encountering one error after another, which is not ideal when I'm attempting to showcase TypeScript to a colleague.

For instance, when I use this basic example (the very first one):

function greeter(name) {
  return 'Hello ' + name;
}

let user = 'Test';

console.log(greeter(user));

Even with this straightforward TypeScript snippet, I end up facing 2 errors.

First Error - The function declaration of 'greeter' is flagged as a 'Duplicate Function Declaration'

Second Error - The declaration of 'user' prompts a 'Cannot redeclare block scoped variable user' message

https://i.sstatic.net/QvUw3.png

I've revisited the guides several times without encountering such problems before.

I've tried disabling any potentially conflicting Plugins like Prettier or ESLint, yet the errors persist.

Initially, I faced challenges due to an incorrect PATH variable that was leading TypeScript to version 1.0.0.3. However, I have corrected this and now have the right TSC version.

Can't seem to understand why I'm getting errors even with such a simple example?

Any tips or suggestions would be greatly appreciated.

Answer №1

It's both frustrating and hilarious that the solution to my problem was so simple. Turns out, having both the .js file and the .ts file open at the same time was causing conflicts.

As soon as I closed one of them, all the errors magically disappeared.

Oh, the joys of coding!

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