charsetSentinel property
final
Enable opt‑in charset detection via the utf8=✓
sentinel.
If present at the start of the input, the sentinel will:
- be omitted from the result map, and
- override charset based on how the checkmark was encoded (UTF‑8 or Latin‑1).
If both charset and charsetSentinel are provided, the sentinel wins when found; otherwise charset is used as the default.
Implementation
final bool charsetSentinel;