Prompt Section Extractor

Parse named prompt sections from explicit boundary markers.

Requirements

• Define extract_sections(text).
• Sections start with a line like <<<name>>>.
• A section ends with a line exactly <<<END>>>.
• Return {"sections": dict, "errors": list}.
• Store section content without the boundary lines.
• Join interior content lines with "\\n". The line that holds <<<END>>> is not part of the body (so a one-line body has no trailing newline). Blank lines before END are preserved as empty lines in the joined body.
• Duplicate section names should produce duplicate:name. On duplicates, keep the first completed section body and append duplicate:<name> while keeping the first stored value unchanged.
• Text outside sections that's not blank should produce outside_text (emit at most once for the whole parse).
• Unterminated sections should produce unterminated:name and must not store a partial body in sections.

Example

Constraints

• Use explicit state tracking.
• Preserve internal newlines inside sections.
• Keep errors deterministic.