bruce@menkar.gsfc.nasa.gov (Bruce Mount 572-8408) (03/21/90)
I am investigating the advantages of ParcPlace's Smalltalk-80 versus the language Eiffel for a commercial product. Since my knowledge of ParcPlace's Smalltalk is out of date, I would appreciate comments from the net. Things I already know: 1. The Smalltalk libarary of classes is much bigger than the Eiffel library. 2. Smalltalk allows arrays elements to contain objects of different classes. 3. The Smalltalk environment is more sophisticated (browsers, etc.). Things I want to know: 1. Does Smalltalk now support multiple inheritence? (I had heard this was under development a while ago, but I haven't kept up to date.) 2. Does Smalltalk offer a tool that allows to to create an "executable" image? Yeah, I know that's not really how Smalltalk works but is there anything that allows you to automatically reduce your image size to the bare minimum once you have a finished product (i.e. remove the code for methods that are never used.) 3. Any stories (good or bad) about personal experience using both Eiffel and Smalltalk. If you wish to make religious statements about either language please try to support them with actual examples. Please reply by e-mail so we don't start a holy war (if you want a holy war there's currently one going on in comp.software-eng). --Bruce ================================================= | Bruce Mount "Brevity is best" | | bruce@atria.gsfc.nasa.gov | =================================================
moss@ibis.cs.umass.edu (Eliot Moss) (03/21/90)
May I suggest that you look into Trellis (formerly called Trellis/Owl or just Owl) from a research group at Digital Equipment? Trellis offers a Smalltalk-like interactive environment (in some ways I think it is *better* than the Smalltalk browser and related tools, including a debugger that lets you set breakpoints, etc.); type-checked, compiled code; and multiple inheritance (with what I view to be the "right" subtyping rules). It also sports multiple activities (lightweight pseudo-processes) and exception handling. It is not a product at this time, but there was a program under which it could be obtained for use, and I know the group still exists. If you're interested I suggest you send mail to Patrick O'Brien (obrien@pbsvax.enet.dec.com). IMHO, Trellis is a better job than Eiffel, and can be viewed (rooughly speaking) as a type-checked version of Smalltalk with a clean model of multiple inheritance. Eliot -- J. Eliot B. Moss, Assistant Professor Department of Computer and Information Science Lederle Graduate Research Center University of Massachusetts Amherst, MA 01003 (413) 545-4206; Moss@cs.umass.edu