Function parse_dlg 

pub fn parse_dlg<D: Directive>(
    file: &str,
    source: &str,
) -> (Vec<ParsedScene<D>>, Vec<ContentError>)

Parses dialogue source (errors attributed to file) into its scenes, in file order, and every syntax error found. A scene with errors in it is still returned (without the broken lines), so later checks can run. A directive the engine doesn’t know is read by the game’s D.