The inablility to work with negative values. Addition can do the following: 5 + (-4) read as 5 plus the value negative four.
Multiplication can do the following: 5 * (-1) read as 5 times the value negative one. String concatination can not subtract the sub-string 'lo' from 'hello'. 'hello' - 'lo' is invalid. string repetition can not repeat a value negative times: 'hello' * -3 is invalid. 'hello' * 2.75 is also invalid, in that you can not repeat a fractional amount. -Dave (Python Newbie) <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] > Greetings. > > I'm reading "How to think like a computer scientist: Learning with > Python" and there's a question regarding string operations. The > question is, "Can you think of a property that addition and > multiplication have that string concatenation and repetition do not?" > > I thought it was the commutative property but "<string>"*3 is > equivalent to 3*"<string>". Any ideas? > > Thanks, > > Jeff > > -- > http://mail.python.org/mailman/listinfo/python-list > -- http://mail.python.org/mailman/listinfo/python-list
