comparison ply-3.8/test/yacc_unicode_literals.py @ 7267:343ff337a19b

<ais523> ` tar -xf ply-3.8.tar.gz
author HackBot
date Wed, 23 Mar 2016 02:40:16 +0000
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7266:61a39a120dee 7267:343ff337a19b
1 # -----------------------------------------------------------------------------
2 # yacc_unicode_literals
3 #
4 # Test for unicode literals on Python 2.x
5 # -----------------------------------------------------------------------------
6 from __future__ import unicode_literals
7
8 import sys
9
10 if ".." not in sys.path: sys.path.insert(0,"..")
11 import ply.yacc as yacc
12
13 from calclex import tokens
14
15 # Parsing rules
16 precedence = (
17 ('left','PLUS','MINUS'),
18 ('left','TIMES','DIVIDE'),
19 ('right','UMINUS'),
20 )
21
22 # dictionary of names
23 names = { }
24
25 def p_statement_assign(t):
26 'statement : NAME EQUALS expression'
27 names[t[1]] = t[3]
28
29 def p_statement_expr(t):
30 'statement : expression'
31 print(t[1])
32
33 def p_expression_binop(t):
34 '''expression : expression PLUS expression
35 | expression MINUS expression
36 | expression TIMES expression
37 | expression DIVIDE expression'''
38 if t[2] == '+' : t[0] = t[1] + t[3]
39 elif t[2] == '-': t[0] = t[1] - t[3]
40 elif t[2] == '*': t[0] = t[1] * t[3]
41 elif t[2] == '/': t[0] = t[1] / t[3]
42
43 def p_expression_uminus(t):
44 'expression : MINUS expression %prec UMINUS'
45 t[0] = -t[2]
46
47 def p_expression_group(t):
48 'expression : LPAREN expression RPAREN'
49 t[0] = t[2]
50
51 def p_expression_number(t):
52 'expression : NUMBER'
53 t[0] = t[1]
54
55 def p_expression_name(t):
56 'expression : NAME'
57 try:
58 t[0] = names[t[1]]
59 except LookupError:
60 print("Undefined name '%s'" % t[1])
61 t[0] = 0
62
63 def p_error(t):
64 print("Syntax error at '%s'" % t.value)
65
66 yacc.yacc()
67
68
69
70