HTML Extraction Language (HEL)

• Tree-based data-model

  • an HTML page is seen as a labeled tree (DOMDocument Object Model)

• Tree navigation via path-expressions (with conditions)

  • extraction rules are described as paths along the tree
  • path expressions always return text values

• Regular expression

  • regular expressions (a la Perl) can be applied on text values to capture finer granularity

<TABLE> <TBODY><TR><TD>Shady Grove</TD><TD>Aeolian</TD></TR><TR><TD>Over the River, Charlie</TD><TD>Dorian</TD></TR></TBODY></TABLE>

HTML

Tree a la DOM

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