decode!

Decode a copied chunk and return its complete text. Incomplete sequences span calls. final=true finishes the stream: a remaining partial sequence raises InvalidUTF8Error or produces one U+FFFD, according to invalid. Further calls after final input or a strict error raise InvalidStateException.

decode!(decoder::TextDecoder, chunk::AbstractVector{UInt8}; final=false)

Error offsets count all input bytes from one, including earlier chunks, and identify the beginning of the malformed subsequence. No I/O occurs. The decoder must not be shared by concurrent callers.