Search Terms

tuple type elements members labels names naming

Suggestion

Currently tuple types are defined like so:

// length, count
type Segment = [number, number];

I often find myself having to add labels to the elements of the tuple as a comment b/c the types themselves (number, string) don't adequately describe what the elements represent.

It would be nice if we could add labels to tuple elements using syntax similar to function parameters like so:

type Segment = [length: number, count: number];

Use Cases

Currently we use comments to describe tuples, but adding this information directly to the AST can provide additional information for tooling.

Examples

This new syntax would also be useful in return types:

function createSegment(/* ... */): [length: number, count: number] {
  /* ... */
}

Checklist

My suggestion meets these guidelines:

• This wouldn't be a breaking change in existing TypeScript / JavaScript code
• This wouldn't change the runtime behavior of existing JavaScript code
• This could be implemented without emitting different JS based on the types of the expressions
• This isn't a runtime feature (e.g. new expression-level syntax)