dlg(1) PCCTS Manual Pages dlg(1)NAMEdlg - DFA Lexical Analyzer Generator
SYNTAXdlg [options] lexical_spec [output_file]
DESCRIPTIONdlg is a tool that produces fast deterministic finite
automata for recognizing regular expressions in input.
OPTIONS-CC Generate C++ output. The output_file is not speci
fied in this case.
-C[ level]
Where level is the compression level used. 0 indi
cations no compression, 1 removes all unused char
acters 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 significantly 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 char
acters identically. This is accomplished in the
automaton; the characters in the lexical buffer are
unmodified.
-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
DLG April 1994 1
dlg(1) PCCTS Manual Pages dlg(1)
match the same character sequence. The warnings
give the numbers of the expressions in the dlg lex
ical specification 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 stan
dard in or send output to standard out.
SPECIAL CONSIDERATIONS
Dlg 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 com
pany may do whatever they wish with source code dis
tributed with PCCTS or the code generated by PCCTS,
including the incorporation of PCCTS, or its output, into
commercial software. We encourage users to develop soft
ware 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 project, or otherwise) that
you acknowledge this fact somewhere in the documentation,
research report, etc... If you like PCCTS and have devel
oped 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 com
pleted.
FILES
mode.h , dlgauto.h , dlgdef.h
SEE ALSOantlr(1), pccts(1)BUGSDLG April 1994 2
