编译原理中的简单算术表达式语法分析器设计

 import re

    
  
    
 # Token types
    
 class TokenType:
    
     ID, NUM, FLOAT, SCIENTIFIC, PLUS, MINUS, MUL, DIV, LPAREN, RPAREN, END, INVALID, NONTERM_E, NONTERM_T, NONTERM_F = range(15)
    
  
    
 # Token class
    
 class Token:
    
     def __init__(self, type_, lexeme):
    
     self.type = type_
    
     self.lexeme = lexeme
    
  
    
 # LR(1) parsing table
    
 lr1_table = {
    
     (0, TokenType.ID): ('S', 5), (0, TokenType.NUM): ('S', 6), (0, TokenType.FLOAT): ('S', 17), (0, TokenType.SCIENTIFIC): ('S', 18), (0, TokenType.LPA