One of the examples in PEP 215 is a bit wrong, I think. >>> print $'\$a' 5 This should output a backslash before the 5, because the string '\$a' has a backslash character in it. Also, for clarity, PEP 215 should explicitly specify that the substitution only occurs once. For example: # Existing examples >>> a, b = 5, 6 >>> print $'a = $a, b = $b' a = 5, b = 6 [...] >>> x = "$a" >>> print $'x = $x' x = $a Maybe there should also be examples demonstrating that $-strings adopt the local namespace. Also, the PEP says: ] $'a = $a, b = $b' ] ] could be compiled as though it were the expression ] ] ('a = ' + str(a) + ', b = ' + str(b)) Consider: def f(str): # The argument 'str' masks the builtin str() function. a, b = find_stuff(str) print $'a = $a, b = $b' return a, b It should be specified that $-strings do not use the local "str" and "unicode" names to find str() and unicode(); nor do they look in the current __builtins__ or the __builtin__ module. They should use the actual python C implementations of str() and unicode(). This can be implemented by putting a direct reference to str or unicode in the co_consts tuple of the code object; I don't know how else the author plans to deal with this. ## Jason Orendorff http://www.jorendorff.com/