Grouping in XSLT David J. Birnbaum Introduction to XSLT for Digital Humanities, Brown University, July 20-22, 2011 Women Writers Project (via website)
mailto:wwp@northeastern.edu

Copyright 2011 David J. Birnbaum and the Women Writers Project

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 Providence, RI USA

Demonstration of grouping in XSLT 2.0
Why use grouping?

Four subtypes: group-starting-with, group-ending-with, group-by, group-adjacent

group-starting-with: unflatten (X)HTML (example to follow) group-by: arrange a bibliography into a hierarchy by author or year group-ending-with and group-adjacent are less common
Marsupials Bilby Koala Wombat
Bilby goes here
Koala goes here
Wombat goes here
Monotremes Echidna Platypus
Echidna goes here
Platypus goes here
An XHTML view of some Australian animals Australian animals

Australian animals

Marsupials

  • Bilby
  • Koala
  • Wombat

Monotremes

  • Echidna
  • Platypus

Task: Find all the marsupials
An XHTML view of some Australian animals Australian animals

Australian animals

Marsupials

  • Bilby
  • Koala
  • Wombat

Monotremes

  • Echidna
  • Platypus

Solution: //li[preceding::h2[1] eq 'Marsupials']

Problem: depends on order and user knowledge of order, which is fragile and non-informational
An XML view of some Australian animals Bilby Koala Wombat Echidna Platypus

Task: Find all the marsupials
An XML view of some Australian animals Bilby Koala Wombat Echidna Platypus

Solution: //order[@label eq 'Marsupials']/animal
Task: Convert XHTML to XML

When and why? You inherit XHTML and want to convert it to something easier to work with and easier to maintain

What’s the problem? Difficult because the input is flat and the output hierarchical

Selects all h2 and li elements

Each h2 begins a new group, which continues until the next h2 or the end of the lis

Refer to the current group as current-group()
Solution