TEXT   10


Guest on 23rd May 2021 08:04:45 AM

  1.                                  Strex Tutorial
  3. I. Introduction.
  5. Strex is a java library for running symbolic tree automata to pattern match
  6. trees.  It is more or less like a regular expression library that is intended
  7. to match text against patterns, except that we match tree structures instead.
  8. Example tree structures are filesystems, xml documents, and syntax trees (both
  9. natural language and formal language).  Users of XPath or other tree query
  10. or tree pattern matching mechanism may find some of this material quite familiar,
  11. and some of it perhaps new.
  13. Strex is intended for use by programmers in a way that programmers may use a
  14. regular expression library.  Correspondingly, the syntax for strex patterns is
  15. quite compact.  This tutorial assumes you can compile and run java programs and
  16. have a text editor of some sort, though we first focus on the issues of trees
  17. and patterns.
  19. II. Trees.
  21. For simplicity of presentation, we will write trees in a simple compact textual
  22. form.  For example, "[a [b c b] a]" is a tree that in filesystem form may look
  23. something like this:
  25.                                     a
  26.                                      |-b
  27.                                      | |-c
  28.                                      | |-b
  29.                                      |-a
  32. While these trees are just abstract data structures, strex is adopted to work
  33. with several different "concrete" trees, such as filesystems, xml documents,
  34. and syntax trees.  We call "a", "b", and "c", the _labels_ of the tree, and
  35. assume that they can be represented as strings of any length.

Raw Paste

Login or Register to edit or fork this paste. It's free.