Marshall <[EMAIL PROTECTED]> wrote: > David Hopwood wrote: > > Marshall wrote:
> > > Mightn't it also be possible to > > > leave it up to the programmer whether a given contract > > > was compile-time or runtime? > > > > That would be possible, but IMHO a better option would be for an IDE to give > > an indication (by highlighting, for example), which contracts are > > dynamically > > checked and which are static. > > > > This property is, after all, not something that the program should depend > > on. > > It is determined by how good the static checker currently is, and we want > > to be > > able to improve checkers (and perhaps even allow them to regress slightly in > > order to simplify them) without changing programs. > > Hmmm. I have heard that argument before and I'm conflicted. > > I can think of more reasons than just runtime safety for which I'd > want proofs. Termination for example, in highly critical code; > not something for which a runtime check will suffice. On the > other hand the points you raise are good ones, and affect > the usability of the language. There doesn't seem to be a point of disagreement here. Programmers often need to require certain properties to be checked at compile-time. Others could go either way. There is no property that a program would rationally desire to *require* be checked at runtime; that would only occur because the compiler doesn't know how to check it at compile time. -- Chris Smith - Lead Software Developer / Technical Trainer MindIQ Corporation -- http://mail.python.org/mailman/listinfo/python-list
