[CM] CM2 vs CM3

[Heinrich Taube]

> 
> Mainly, what are the main differences between CM2 and CM3, design and
> composition wise? I know that version 3 uses Scheme instead of Common
> Lisp, so CLOS isn't used anymore, but what kind of changes has this
> brought to CM?

hi in terms of the changes to the cm 'language' between 2 and 3 the main design change was replacing clos -- which cm2 uses pervasively -- with lightweight scheme functions and a few structs for important persistent data like patterns.  this allowed me to move from a very expressive but non-realtime, non-gui, consy  environment (common lisp) to a more flexible lightweight environment that mixes lisp (s7 scheme) with real-time scheduler and graphics in C++.  in a nutshell, then , the basic functionally between cm2 and cm3 has been preserved but with name changes (for example no generic functions…)

> I will be acquiring a copy of Notes from the Metalevel soon, and want
> to know if I can follow the book using CM3 instead of version 2, if I
> might choose to go with Scheme in my projects. Or if I choose to go
> with Common Lisp, are there any drawbacks in using Common Music 2?
> Will I be missing out on something?

the book examples are closer to cm2 than cm3. I'm actually talking with the publisher about a second edition, which would certainly be sal and scheme.  the book did pretty well by academic standards but honestly I'm not sure how many people are interested in this sort of book any more. Numbers don't say the whole thing (or even half the thing), but at some level its important to feel that the outcome is worth the 'lift'.  regardless i do plan to recast all examples in Notes into sal and scheme.