switch to using enumerate() for looping over numbers where needed

arthurdejong · arthurdejong · commit 4017d83edd8d · 2010-08-26T21:03:44.000Z
git-svn-id: http://arthurdejong.org/svn/python-stdnum/python-stdnum@34 9dea7c4f-944c-4273-ac1a-574ede026edc
diff --git a/stdnum/isbn/__init__.py b/stdnum/isbn/__init__.py
@@ -51,13 +51,13 @@ def compact(number):
 def _calc_isbn10_check_digit(number):
     """Calculate the ISBN check digit for 10-digit numbers. The number passed
     should not have the check bit included."""
-    check = sum( (i + 1) * int(number[i]) for i in range(len(number)) ) % 11
+    check = sum( (i + 1) * int(n) for i, n in enumerate(number) ) % 11
     return 'X' if check == 10 else str(check)
 
 def _calc_isbn13_check_digit(number):
     """Calculate the ISBN check digit for 13-digit numbers. The number passed
     should not have the check bit included."""
-    return str((10 - sum( (2 * (i % 2) + 1) * int(number[i]) for i in range(len(number)))) % 10)
+    return str((10 - sum( (2 * (i % 2) + 1) * int(n) for i, n in enumerate(number))) % 10)
 
 def isbn_type(number):
     """Check the passed number and returns 'ISBN13', 'ISBN10' or None (for
diff --git a/stdnum/ismn.py b/stdnum/ismn.py
@@ -48,7 +48,7 @@ def compact(number):
 def _calc_check_digit(number):
     """Calculate the ISMN check digit. The number passed should not have
     the check bit included and should be in the 13-digit form."""
-    return str((10 - sum( (2 * (i % 2) + 1) * int(number[i]) for i in range(len(number)))) % 10)
+    return str((10 - sum( (2 * (i % 2) + 1) * int(n) for i, n in enumerate(number))) % 10)
 
 def is_valid(number):
     """Checks to see if the number provided is a valid ISMN (either a legacy
diff --git a/stdnum/issn.py b/stdnum/issn.py
@@ -40,7 +40,7 @@ def compact(number):
 def _calc_check_digit(number):
     """Calculate the ISSN check digit for 10-digit numbers. The number passed
     should not have the check bit included."""
-    check = (11 - sum( (8 - i) * int(number[i]) for i in range(len(number)) ) ) % 11
+    check = (11 - sum( (8 - i) * int(n) for i, n in enumerate(number) ) ) % 11
     return 'X' if check == 10 else str(check)
 
 def is_valid(number):
diff --git a/stdnum/verhoeff.py b/stdnum/verhoeff.py
@@ -66,8 +66,8 @@ def checksum(number):
     number = tuple( int(n) for n in reversed(str(number)) )
     # calculate checksum
     check = 0
-    for i in range(len(number)):
-        check = _multiplication_table[check][_permutation_table[i % 8][number[i]]]
+    for i, n in enumerate(number):
+        check = _multiplication_table[check][_permutation_table[i % 8][n]]
     return check
 
 def is_valid(number):
