1 files changed, 41 insertions, 26 deletions

diff --git a/example/optcalc/calc.py b/example/optcalc/calc.py
index dd83351..0c223e5 100644
--- a/example/optcalc/calc.py
+++ b/example/optcalc/calc.py
@@ -6,27 +6,28 @@
 # -----------------------------------------------------------------------------
 
 import sys
-sys.path.insert(0,"../..")
+sys.path.insert(0, "../..")
 
 if sys.version_info[0] >= 3:
     raw_input = input
 
 tokens = (
-    'NAME','NUMBER',
-    'PLUS','MINUS','TIMES','DIVIDE','EQUALS',
-    'LPAREN','RPAREN',
-    )
+    'NAME', 'NUMBER',
+    'PLUS', 'MINUS', 'TIMES', 'DIVIDE', 'EQUALS',
+    'LPAREN', 'RPAREN',
+)
 
 # Tokens
 
-t_PLUS    = r'\+'
-t_MINUS   = r'-'
-t_TIMES   = r'\*'
-t_DIVIDE  = r'/'
-t_EQUALS  = r'='
-t_LPAREN  = r'\('
-t_RPAREN  = r'\)'
-t_NAME    = r'[a-zA-Z_][a-zA-Z0-9_]*'
+t_PLUS = r'\+'
+t_MINUS = r'-'
+t_TIMES = r'\*'
+t_DIVIDE = r'/'
+t_EQUALS = r'='
+t_LPAREN = r'\('
+t_RPAREN = r'\)'
+t_NAME = r'[a-zA-Z_][a-zA-Z0-9_]*'
+
 
 def t_NUMBER(t):
     r'\d+'
@@ -39,14 +40,16 @@ def t_NUMBER(t):
 
 t_ignore = " \t"
 
+
 def t_newline(t):
     r'\n+'
     t.lexer.lineno += t.value.count("\n")
-    
+
+
 def t_error(t):
     print("Illegal character '%s'" % t.value[0])
     t.lexer.skip(1)
-    
+
 # Build the lexer
 import ply.lex as lex
 lex.lex(optimize=1)
@@ -54,45 +57,57 @@ lex.lex(optimize=1)
 # Parsing rules
 
 precedence = (
-    ('left','PLUS','MINUS'),
-    ('left','TIMES','DIVIDE'),
-    ('right','UMINUS'),
-    )
+    ('left', 'PLUS', 'MINUS'),
+    ('left', 'TIMES', 'DIVIDE'),
+    ('right', 'UMINUS'),
+)
 
 # dictionary of names
-names = { }
+names = {}
+
 
 def p_statement_assign(t):
     'statement : NAME EQUALS expression'
     names[t[1]] = t[3]
 
+
 def p_statement_expr(t):
     'statement : expression'
     print(t[1])
 
+
 def p_expression_binop(t):
     '''expression : expression PLUS expression
                   | expression MINUS expression
                   | expression TIMES expression
                   | expression DIVIDE expression'''
-    if t[2] == '+'  : t[0] = t[1] + t[3]
-    elif t[2] == '-': t[0] = t[1] - t[3]
-    elif t[2] == '*': t[0] = t[1] * t[3]
-    elif t[2] == '/': t[0] = t[1] / t[3]
-    elif t[2] == '<': t[0] = t[1] < t[3]
+    if t[2] == '+':
+        t[0] = t[1] + t[3]
+    elif t[2] == '-':
+        t[0] = t[1] - t[3]
+    elif t[2] == '*':
+        t[0] = t[1] * t[3]
+    elif t[2] == '/':
+        t[0] = t[1] / t[3]
+    elif t[2] == '<':
+        t[0] = t[1] < t[3]
+
 
 def p_expression_uminus(t):
     'expression : MINUS expression %prec UMINUS'
     t[0] = -t[2]
 
+
 def p_expression_group(t):
     'expression : LPAREN expression RPAREN'
     t[0] = t[2]
 
+
 def p_expression_number(t):
     'expression : NUMBER'
     t[0] = t[1]
 
+
 def p_expression_name(t):
     'expression : NAME'
     try:
@@ -101,6 +116,7 @@ def p_expression_name(t):
         print("Undefined name '%s'" % t[1])
         t[0] = 0
 
+
 def p_error(t):
     if t:
         print("Syntax error at '%s'" % t.value)
@@ -116,4 +132,3 @@ while 1:
     except EOFError:
         break
     yacc.parse(s)
-