HTML association table extractor

HTML association table extractor is a cousin of HTML property table extractor. Both read simple HTML fragments containing table, tr, and td elements and convert table content to associations.

HTML association table extractor interprets first table row as a list of roles used in associations. Subsequent table rows are interpreted as associations. Each table cell is interpret either as a role or a player of the association.

Extractor can't handle cell merges caused by cellspan and rowspan attributes used in HTML table elements. Also, the extractor doesn't handle nested HTML tables.