import re
Here's an outline of an interesting report on compiler design based on the book:
# Token types INTEGER, PLUS, MINUS, EOF = 'INTEGER', 'PLUS', 'MINUS', 'EOF'
# Example usage lexer = Lexer('2 + 3') token = lexer.get_next_token() compiler design book of aa puntambekar pdf 71 2021
def __repr__(self): return f'Token({self.type}, {self.value})'
# Lexer class class Lexer: def __init__(self, text): self.text = text self.pos = 0 self.current_char = self.text[self.pos]
Hope this helps!
def skip_whitespace(self): while self.current_char is not None and self.current_char.isspace(): self.advance()
Here is sample code for lexical analyzer
return Token(EOF, None)
def integer(self): result = '' while self.current_char is not None and self.current_char.isdigit(): result += self.current_char self.advance() return int(result)
if self.current_char == '-': self.advance() return Token(MINUS, '-')