On 13 dec, 12:28, Steven D'Aprano <steve +comp.lang.pyt...@pearwood.info> wrote: > On Tue, 13 Dec 2011 02:46:13 -0800, Eelco wrote: > > With all this being said, I must say that the notion of indtroducing > > type constraints into Python is quite a radical one*, > > Not that radical. Here's the creator of Python musing about adding > optional type checks to Python: > > http://www.artima.com/weblogs/viewpost.jsp?thread=85551http://www.artima.com/weblogs/viewpost.jsp?thread=86641http://www.artima.com/weblogs/viewpost.jsp?thread=87182
Good find; but still radical enough that it hasnt been implemented. Note that these musing are trying to adress a yet far more general problem of specifying arbitrary types constraints on anything; I am primarily interested in specifying container types in the special case of collection packing/unpacking syntax, with further extensions nothing but a welcome addon. The fact that the former was judged infeasible does not mean the more modest goal of the latter might not be attainable. > > *even though the asteriks syntax is infact a limited form of exactly > > that > > It absolutely is not. def f(*args, **kwargs) constructs a tuple and a > dict, it does not type-check that the function is passed a tuple and a > dict as arguments. These are completely different things. Which is of course not something I ever proposed; I never said anything about checking types of existing data; im talking about coercing types of newly created data, like the target of a collection packing. That is exactly what *args and **kwargs also do. -- http://mail.python.org/mailman/listinfo/python-list
