The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type.ts(2363)

Suggestion

The following code errors:

      const x: Number = 5;
      const y = 5 - x;

With this:

The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type.ts(2363)

Which is super confusing because it is a number. But I didn't realize the problem was the first letter capitalization. Number vs number.

🔍 Search Terms

right-hand side of an arithmetic

✅ Viability Checklist

My suggestion meets these guidelines:

• [v] This wouldn't be a breaking change in existing TypeScript/JavaScript code
• [v] This wouldn't change the runtime behavior of existing JavaScript code
• [v] This could be implemented without emitting different JS based on the types of the expressions
• [v] This isn't a runtime feature (e.g. library functionality, non-ECMAScript syntax with JavaScript output, new syntax sugar for JS, etc.)
• [v] This feature would agree with the rest of TypeScript's Design Goals.

⭐ Suggestion

Would be nice if there was an error during the assignment, is Number also a number? Another option is error 2363 could mention this potential issue. E.g.

The right-hand side of an arithmetic operation must be of type 'any', 'number', 'bigint' or an enum type. Not 'Number' .ts(2363)

And replace 'Number' with whatever type was actually found.

📃 Motivating Example

      const x: Number = 5;
      const y = 5 - x;

Minor typos should have a clear error message.

Beginne damit, Diagnostic 2363 im TypeScript-Compiler und die Tests zu finden, die Fehler bei arithmetischen Operationen abdecken. Bestätige, wie der gemeldete Operandentyp ausgewählt wird, und aktualisiere anschließend das Verhalten der Diagnostic so, dass ein Typ wie 'Number' identifiziert wird, und ergänze Tests für das motivierende Beispiel.