In this homework you are to implement lexer and parser for a simple language.
Token definitions:
ID = [A-Z]+
LAPR = (
RPAR = )
NOT=!
AND = /\
OR=\/
IMPLIES = ‘=>’
IFF = ‘<=>’
Grammar:
propositions → proposition more-proposition
more-proposition → , propositions |
proposition → atomic | compound
atomic → 0 | 1 | ID
compound → atomic connective proposition | LPAR proposition RPAR | NOT proposition connective → AND | OR | IMPLIES | IFF
The start variable is propositions.
Your implementation should receive a file, if the input file is a valid program, it should print the parse tree in prefix order, otherwise it should return “Syntax Error” message along with the line and column numbers of the first error.
Instructions:
• Use Python 2.7 for implementation
• Deadline: Feb 11 at 9 AM
