Proposal: Use [string, ...string[]] for Catch-all Segments PageProps type definition

[y-hsgw]

Goals

1. Improve the accuracy of TypeScript type definitions for Catch-all Segments ([...slug]), reflecting the actual runtime behavior.

Non-Goals

Background

• PageProps defines Catch-all Segments ([...slug]) as params: { slug: string[] }.
• However, at runtime, accessing a Catch-all route always includes at least one segment — for example:
  • /post/a → params.slug = ['a']
  • /post/a/b → params.slug = ['a', 'b']
  • /post/ → returns 404

Proposal

Update the PageProps type definition for Catch-all Segments ([...slug]) .

from:

params: { slug: string[] }

to:

params: { slug: [string, ...string[]] }