Hi Denis, On Tue, May 9, 2017 at 12:51 PM, Denis Kudriashov <dionisi...@gmail.com> wrote:
> Hi Eliot. > > 2017-05-09 21:27 GMT+02:00 Eliot Miranda <eliot.mira...@gmail.com>: > >> Hmmm, classNamed: has always answered nil for nonexistent classes. Did >> this get changed? Not sure that's right. Why not add checkedClassNamed: >> or some such? > > > I created this issue. I am sure that returning nil from methods is always > bad design and many books describe it. > Also it is not consistent to #at: method: > > Smalltalk globals at: #AbsentClass. "=> raise error" > Smalltalk globals classNamed: #AbsentClass "=> nil" > > I get that. But there's lots of code out there that expects classNamed: to answer nil for names tat don't name a class. Why break all that code? If you had added checkedClassNamed: or some thing else then that old code wouldn't be broken. There needs to be some cheap way of checking whether a class with a specific name actually exists. classNamed: fulfilled that need. By redefining it you'e meant that that has to be reimplemented. It's not a good idea to redefine co=re behavior in this way. It breaks lots of code (including VMMaker). -- _,,,^..^,,,_ best, Eliot
