


dlg(1)                 PCCTS Manual Pages                  dlg(1)



NAME
     dlg - DFA Lexical Analyzer Generator

SYNTAX
     dlg [_o_p_t_i_o_n_s] _l_e_x_i_c_a_l__s_p_e_c [_o_u_t_p_u_t__f_i_l_e]

DESCRIPTION
     dlg is a tool that produces fast deterministic finite auto-
     mata for recognizing regular expressions in input.

OPTIONS
     -CC  Generate C++ output.  The _o_u_t_p_u_t__f_i_l_e is not specified
          in this case.

     -C[ level]
          Where level is the compression level used.  0 indica-
          tions no compression, 1 removes all unused characters
          from the transition from table, and 2 maps equivalent
          characters into the same character classes.  It is sug-
          gested that level -C2 is used, since it will signifi-
          cantly reduce the size of the dfa produced for lexical
          analyzer.

     -m   Produces the header file for the lexical mode with a
          name other than the default name of "mode.h".

     -i   An interactive, or as interactive as possible, parser
          is produced.  A character is only obtained when
          required to decide which state to go to.  Some care
          must be taken to obtain accept states that do not
          require look ahead at the next character to determine
          if that is the stop state.  Any regular expression with
          a Kleene closure at the end is guaranteed to require
          another character of look ahead.

     -cl class
          Specify a class name for DLG to generate.  The default
          is DLGLexer.

     -ci  The automaton will treat upper and lower case charac-
          ters identically.  This is accomplished in the automa-
          ton; the characters in the lexical buffer are unmodi-
          fied.

     -cs  Upper and lower case characters are treated as dis-
          tinct.  This is the default.

     -o dir
          Directory where output files should go (default=".").
          This is very nice for keeping the source directory
          clear of ANTLR and DLG spawn.

     -Wambiguity
          Warns if more than one regular expression could match
          the same character sequence.  The warnings give the
          numbers of the expressions in the dlg lexical specifi-
          cation file.  The numbering of the expressions starts
          at one.  Multiple warnings may be print for the same
          expressions.

     -    Used in place of file names to get input from standard
          in or send output to standard out.

SPECIAL CONSIDERATIONS
     _D_l_g works...  we think.  There is no implicit guarantee of
     anything.  We reserve no legal rights to the software known
     as the Purdue Compiler Construction Tool Set (PCCTS) - PCCTS
     is in the public domain.  An individual or company may do
     whatever they wish with source code distributed with PCCTS
     or the code generated by PCCTS, including the incorporation
     of PCCTS, or its output, into commercial software.  We
     encourage users to develop software with PCCTS.  However, we
     do ask that credit is given to us for developing PCCTS.  By
     "credit", we mean that if you incorporate our source code
     into one of your programs (commercial product, research pro-
     ject, or otherwise) that you acknowledge this fact somewhere
     in the documentation, research report, etc...  If you like
     PCCTS and have developed a nice tool with the output, please
     mention that you developed it using PCCTS.  As long as these
     guidelines are followed, we expect to continue enhancing
     this system and expect to make other tools available as they
     are completed.

FILES
     mode.h , dlgauto.h , dlgdef.h

SEE ALSO
     antlr(1), pccts(1)

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