Re: Reference and First-Class Function

> Regardless of our own preferences we must not force a 
> developer into a single "best" option without alternatives. 
...
> 
> Overspecification is harmful -- should this fact be repeated again?
> 

When you're designing a language I think it's important to minimize the set
of fundamental concepts, that is, concepts that can't be defined in terms of
other concepts. Good architectural layering is the essence of good software
specification and design. One of the main reasons for introducing HOF into
the foundations is that it allows many other things to be layered on top,
including such things as references, nested sequences, dictionaries, etc,
with less effort and complexity than if they were defined as primitives.
This is not overspecification: it's simply good architecture. And it's not
constraining implementors, either; the fact that we've layered the
specification in a particular way doesn't force implementors to layer their
implementations in the same way.

Michael Kay
http://www.saxonica.com/