Simon Forman schreef: > I've been programming in python for years and I've always used this > form > > if not seq: > if seq: > > rather than the other and never had any problems. > > Anyone presenting arguments in favor of the len() form is IMHO, not > "getting it". AFAIK, python is not "smart" enough to optimize away the > (totally unnecessary) call to len(), so the programmer should do it for > herself. > > The "pythonic" form is safe, not weird, and just as explicit.
I know that that is the consensus, and I mostly the form without len(), but somehow I still feel it is not as explicit. In if seq: there is no distinction between seq is None on the one hand and seq being a valid empty sequence on the other hand. I feel that that is an import distinction, and it's the reason I find myself using len() from time to time (even though I can't think of a use case right now). -- If I have been able to see further, it was only because I stood on the shoulders of giants. -- Isaac Newton Roel Schroeven -- http://mail.python.org/mailman/listinfo/python-list
