On Fri, Oct 04, 2002 at 09:13:45AM -0400, Chris Dutton wrote: > > How exactly does one "weaken" a precondition? > > At least in Eiffel, if you redefine a method, you may not give it > stringer preconditions than the original method, but you may have > stronger postconditions. In essence, you're not requiring any more of > the client, but you can ensure more to them on completion, thus > maintaining the parent's contract.
But what does it mean to be "stronger"? How does Eiffel figure out if a given precondition is "stronger" or "weaker" than another? -- Michael G Schwern <[EMAIL PROTECTED]> http://www.pobox.com/~schwern/ Perl Quality Assurance <[EMAIL PROTECTED]> Kwalitee Is Job One
