[Guido]
For strings there is no compact notation like "+0.0" if you want to convert to string or Unicode -- adding "" might work in Perl, but not in Python.
BTW, "+0.0" is not a correct way to "boundedly coerce" to float under 754 arithmetic; "*1.0" is safer (the former does not always preserve the sign bit of a float zero correctly, but the latter does). [Paul Prescod]
Actually, these days, foo+"" works in a LOT of languages. Perl, Java and JavaScript for sure.
[Guido]
Really? Does 3+"" really convert the 3 to a string in Java?
I don't remember about that specifically, but believe ""+3 does. OTOH, in *Perl* 3+"" converts "" to the *number* 0 and leaves 3 alone.
Python's strictness about this issue has never caught a bug for me. It has only caused errors.
Are you sure? This is the kind of error where you immediately see what's wrong and move on to the next bug.
It's certainly caught errors for me, and especially when introducing Perl programmers to Python, where "they expect" string+number to convert the string to a number, apparently the opposite of the arbitrary choice Paul prefers. It's ambiguous as hell -- screw it.