package web

import "io/fs"

// mustSub returns an FS rooted at dir within root, panicking on error (dir
// is always a compile-time-known embedded path, so this can only fail if the
// embed itself is misconfigured).
func mustSub(root fs.FS, dir string) fs.FS {
	sub, err := fs.Sub(root, dir)
	if err != nil {
		panic(err)
	}
	return sub
}