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)

BUGS