


dlg - DFA Lexical Analyzer Generator

dlg [ -C [ level ] ] [  -m  mode_file  ]  [  -i  ]  [  -cs  or  -ci  ]
lexical_spec output_file

dlg is a tool that produces fast  deterministic  finite  automata  for
recognizing regular expressions in input.

-C[level] Where level is the compression level used.  0 indications no
compression,  1 removes all unused characters from the transition from
table, and 2  maps  equivalent  characters  into  the  same  character
classes.  It is suggested that level -C2 is used, since it will signi-
ficantly 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 char-
acter 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.  -ci The automaton will treat upper and lower
case  characters  identically.  This is accomplished in the automaton;
the characters in the lexical buffer are unmodified.   -cs  Upper  and
lower  case  characters are treated as distinct.  This is the default.
- Used in place of file names to get input from standard  in  or  send
output to standard out.


     Dlg works...  we think.  There is no implicit guarantee  of  any-
thing.  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 commerical
software.  We encourage users to develop software  with  PCCTS.   How-
ever,  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 project, 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 con-
tinue enhancing this system and expect to make other  tools  available
as they are completed.

mode.h , dlgauto.h , dlgdef.h











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