[armedbear-devel] some questions about r12503

[Ville Voutilainen]

On 22 February 2010 22:20, Mark Evenson <evenson at panix.com> wrote:

First of all, an excellent explanation for the implementation choices. Thanks!

> I am a "if the function doesn't fit into one 80x25 Emacs buffer it
> should be split" kinda guy", but the ABCL codebase violates that maxim
> at so many points (q.v. compiler-pass2.lisp) that I don't try to

The violation is cruft in our codebase, and is something we are semi-actively
gettind rid of. I've been trying to shorten things wherever I touch,
Closure.java
being the prime example of such work. compiler-pass2 is actually another
example. Note that both pass2 and Closure still have long functions in places,
but we have cut a lot of that cruft into better abstractions whenever time has
allowed.

> religously follow that principle here.  I'd be happy to do such
> splitting, but would have thought that you of all people would have
> jumped on my back about the penalty for a further push to the stack.  My

Oh, not at all - I expect the compiler to inline the calls to the
(hopefully forthcoming)
two helper functions. I prefer readability to micro-optimizations any
given day. :)
I prefer readability to even _real_ optimizations.

> splitting is worth it.  But for functions like LIST-DIRECTORY, we should
> keep it all in one method call for efficiency.  For what its worth, I

That would sound like a premature optimization to me. Having LIST-DIRECTORY
as

if (jar) {
  listJar();
} else {
  listDir();
}

should be just fine, if the separate helper functions are private. As
I said, I expect
the compiler to inline such calls.