Convert Code From Python 2.x To 3.x

This is a followup on my previous question, I am using the 2to3 tool as suggested by Senthil Kumaran It seems to work well but it doesn't pick up this part: raise LexError,('%s:%d:

Solution 1:

The func_code attribute of functions has been renamed to __code__, so try

func.__code__.co_filename, func.__code__.co_firstlineno,

as the second line of your code snippet.

Solution 2:

Remove the comma after LexError. That works in both Python 2 and Python 3.

In Python 2 there was a rarely used syntax to raise exceptions like this:

raise ExceptionClass, "The message string"

This is the one used here, but for some reason, maybe since there is a parenthesis around the message string (according to Senthils tests, it's the line break in the parenthesis that does it), 2to3 misses the change into the much better:

raise ExceptionClass("The message string")

So it should look like this (in Python 2)

message = "%s:%d: Rule '%s' returned an unknown token type '%s'" % (
           func.func_code.co_filename, func.func_code.co_firstlineno,
           func.__name__, newtok.type),lexdata[lexpos:])
raise LexError(message)

Because formatting that message on the same line as the raise is fugly. :-) Then in addition func_code has been renamed, so in Python 3 there are more changes. But with the above change 2to3 should work correctly.

Solution 3:

What problem are you getting? 2to3 seems to translate it for me fine.

-    raise LexError,("%s:%d: Rule '%s' returned an unknown token type '%s'" % (func.func_code.co_filename,func.func_code.co_firstlineno,func.__name__,newtok.type),lexdata[lexpos:])
+    raise LexError("%s:%d: Rule '%s' returned an unknown token type '%s'" % (func.__code__.co_filename,func.__code__.co_firstlineno,func.__name__,newtok.type),lexdata[lexpos:])