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Emacs Syntax Tables
-------------------

  A "syntax table" is an array indexed by the characters in your
character set.  In the ASCII encoding, therefore, a syntax table has
256 elements.

  If Regex is compiled with the preprocessor symbol `emacs' defined,
then Regex expects you to define and initialize the variable
`re_syntax_table' to be an Emacs syntax table.  Emacs' syntax tables
are more complicated than Regex's own (*note Non-Emacs Syntax
Tables::.).  syntax tables.