file

$file

Validates that a path exists in the filesystem and is a file (not a directory or other type). Performs an asynchronous filesystem check using fs.stat().

• Non-existent paths: "/does/not/exist.txt" → throws "File does not exist"
• Directory paths: "/var/log" → throws "Path exists but is not a file"
• Inaccessible paths: "/root/secret.txt" (permission denied) → throws "Cannot access file: ..."