From a0ce00f1245aeabfc83c0d962e3b3b6b43bc2246 Mon Sep 17 00:00:00 2001
From: streetartist <60282562+streetartist@users.noreply.github.com>
Date: Sun, 6 Sep 2020 06:53:52 +0800
Subject: [PATCH] Add a support with string

---
 src/main.py | 64 +++++++++++++++++++++++++++++++++++------------------
 1 file changed, 42 insertions(+), 22 deletions(-)

diff --git a/src/main.py b/src/main.py
index 9ea4c3f..8d6b2c9 100644
--- a/src/main.py
+++ b/src/main.py
@@ -12,9 +12,9 @@ def run(string: str) -> str:
 '''
 
 from rply import LexerGenerator
-
+ 
 lg = LexerGenerator()
-
+ 
 lg.add('NUMBER', r'\d+')
 lg.add('PLUS', r'\+')
 lg.add('MINUS', r'-')
@@ -23,51 +23,58 @@ def run(string: str) -> str:
 lg.add('OPEN_PARENS', r'\(')
 lg.add('CLOSE_PARENS', r'\)')
 lg.add('PRINT',r'print')
-
+lg.add('STRING',r'"\w"')
+ 
 lg.ignore('\s+')
-
+ 
 lexer = lg.build()
-
+ 
 from rply.token import BaseBox
-
+ 
 class Number(BaseBox):
     def __init__(self, value):
         self.value = value
-
+ 
     def eval(self):
         return self.value
         
-
+class String(BaseBox):
+    def __init__(self, value):
+        self.value = value
+ 
+    def eval(self):
+        return self.value
+ 
 class BinaryOp(BaseBox):
     def __init__(self, left, right):
         self.left = left
         self.right = right
-
+ 
 class Add(BinaryOp):
     def eval(self):
         return self.left.eval() + self.right.eval()
-
+ 
 class Sub(BinaryOp):
     def eval(self):
         return self.left.eval() - self.right.eval()
-
+ 
 class Mul(BinaryOp):
     def eval(self):
         return self.left.eval() * self.right.eval()
-
+ 
 class Div(BinaryOp):
     def eval(self):
         return self.left.eval() / self.right.eval()
-
+ 
 class Print(BinaryOp):
 	def eval(self):
-		print(self.right.eval())
-
+		return self.right.eval()
+ 
 from rply import ParserGenerator
-
+ 
 pg = ParserGenerator(
     # A list of all token names, accepted by the parser.
-    ['NUMBER', 'OPEN_PARENS', 'CLOSE_PARENS',
+    ['NUMBER','STRING', 'OPEN_PARENS', 'CLOSE_PARENS',
      'PLUS', 'MINUS', 'MUL', 'DIV','PRINT'
     ],
     # A list of precedence rules with ascending precedence, to
@@ -78,17 +85,23 @@ def eval(self):
         ('right',['PRINT'])
     ]
 )
-
+ 
 @pg.production('expression : NUMBER')
 def expression_number(p):
     # p is a list of the pieces matched by the right hand side of the
     # rule
     return Number(int(p[0].getstr()))
 
+@pg.production('expression : STRING')
+def expression_number(p):
+    # p is a list of the pieces matched by the right hand side of the
+    # rule
+    return String(p[0].getstr())
+   
 @pg.production('expression : OPEN_PARENS expression CLOSE_PARENS')
 def expression_parens(p):
     return p[1]
-
+ 
 @pg.production('expression : expression PLUS expression')
 @pg.production('expression : expression MINUS expression')
 @pg.production('expression : expression MUL expression')
@@ -106,15 +119,22 @@ def expression_binop(p):
         return Div(left, right)
     else:
         raise AssertionError('Oops, this should not be possible!')
-
+ 
 @pg.production('expression : PRINT expression')
 def expression_func(p):
 	right = p[1]
 	if p[0].gettokentype() == 'PRINT':
 		return Print(None, right)
-
+ 
 parser = pg.build()
-
+ 
 @pg.error
 def error_handler(token):
     raise ValueError("Ran into a %s where it wasn't expected" % token.gettokentype())
+    
+
+while(True):
+	try:
+		print(parser.parse(lexer.lex(input(">>>"))).eval())
+	except Exception as e:
+			print(e)