# Copyright (C) Mohammad Hasanzadeh Mofrad - All Rights Reserved
# Course: CS 2210 - Compiler Design (Spring 2016)
# Project: Mini Java - part 1 - Lexical Analyzer
# File: Readme
# Author: Mohammad Hasanzadeh Mofrad
# Email: hasanzadeh@cs.pitt.edu
# Date: January 2016; Last revision 01-28-2016

## Project structure
This project consists of four key files:
* Makefile that build the program
* lexer.l that contains the followings:
	- Regular expressions
	- String table which stores identifies and string constants
	- Error handling
* driver.c that catch and print the output of lexer.l.
* tokens.h that contains the token numbers of reserved words

## Lexer specifications
The lexer consist of a set of regular expressions for detecting the following token types:
* Identifies
* Integer constants
* String constants
* Reserved words
* Escape sequence characters: "\n", "\t", "\'", "\\"
* Comments

## Error handling
* yyerror method handles the following errors:
* Malformed identifier
* Malformed integer constants
* Malformed string constant
* Malformed comments
* Unsupported characters

## Optimizations
* Design to work with yytext, yylegn, yyline, yycolumnno, yylval, and yyin global variables
* String table (yystrtbl method) stores the identifiers and string constant values and separates them by using '\0' delimiter
* String table returns the same yylval for similar tokens
* Type table stores the type of stored tokens
* Remove spaces from left and right hand sides of a string constant
* Allow null string constant
* Allow empty string constant
* No third part library is used