Description

This was a project for my Compilers class at CSULA. It mirrors the C- Minus Project and incorporates the grammar rules established from that project. Essentially, when given a grammar it will output the state rules and all of that relevent information used to get to those rules.

Table of Contents

• Key Features
• Installation
• Functionality
  • Input
  • Output
  • Writing To File
• Support

Key Features

• Takes in a grammar, but must have a specific format (detailed below)
• Handles epsilons
• Option to output to console or file
• Outputs:
  • Terminals
  • Non-Terminals
  • First Set
  • Follow Set
  • State Set

Installation

This project is designed to run within any Java IDE. I was using IntelliJ IDEA, so one can clone the project and run it in IntelliJ IDEA. Or, alternatively, one could just download the source files individually and run the project from any IDE.

Functionality

Input

The input for the Grammar must be formatted as such, where the rule can be separated by '::' or '->':

A :: S A S
A :: A S A
A :: b
A -> a
S -> A S A
S -> empty

Within the actual code itself, there are already 8 available test Grammars. You can either copy the instantiation line to create a 9th Grammar and include the appropraite file in the 'GrammarFiles' folder, or simply edit an existing one.

// select which grammar you'd like to run here
// Grammar grammar = new Grammar("GrammarFiles/GrammarList1.txt");
// Grammar grammar = new Grammar("GrammarFiles/GrammarList2.txt");
.....
Grammar grammar = new Grammar("GrammarFiles/GrammarList8.txt");

Output

For the output, in the state generation section, commands G, S and R stand for goto, state and reduce, respectfully. The output will print out the following information in this format:

========== TERMINALS =============
a
b
========== NONTERMINALS ==========
A
S
========== PRODUCTION ============
A :: S A S
A :: A S A
A :: b
A :: a
S :: A S A
S :: empty
========== AUGMENTED PRODUCTION ==========
A' :: A
A :: S A S
A :: A S A
A :: b
A :: a
S :: A S A
S ::
========== FIRST SET  ==========
A :: a b empty
S :: a b empty
========== FOLLOW SET ==========
A :: a b $
S :: a b $
========== STATE SET ==========
----------------- State 0 --------------------
A' :: # A
A :: # S A S
A :: # A S A
A :: # b
A :: # a
S :: # A S A
S :: #

----------------- State 1 --------------------
A' :: A #
A :: A # S A
S :: A # S A
S :: #

.....
.....
.....
.....
.....

----------------- State 9 --------------------
A :: S A S #
A :: A S # A
S :: # A S A
S :: #

---------- State 0 ----------
Symbol  A
Command G
Number  1

Symbol  $
Command R
Number  6

---------- State 1 ----------
Symbol  S
Command G
Number  5

Symbol  $
Command accept

---------- State 2 ----------
Symbol  A
Command G
Number  7

Symbol  S
Command G
Number  2

.....
.....
.....
.....
.....

---------- State 9 ----------
Symbol  A
Command G
Number  8

Symbol  $
Command R
Number  6

Writing to File

Be default, these lines of code will print everything to the console:

// prints first and follow to console
parser.printFirstToConsole();
parser.printFollowToConsole();

// prints all states to console
slrstate.printToConsole();

// prints slr table to console
slrtable.printToConsole();

However, if you uncomment these lines, it will also print to file:

// prints first and follow to file
// parser.printFirstToFile();
// parser.printFollowToFile();

// prints all states to file
// slrstate.printToFile();

// prints slr table to file
// slrtable.printToFile();

Support

More comments and efficiency updates.

But, if it breaks, you can keep both pieces.