[asdf-devel] The Manual

[Faré]

On 3 October 2010 17:18, Dave Penton <djp at arqux.com> wrote:
> A manual section on the
> semantics of defsystem is sorely needed. I am fairly new to Common Lisp (one
> year). Like most developers I need some kind of system definition facility
> but find myself a bit exasperated learning to use asdf.
>
There is no well-defined semantics beyond what the code does.
What do you need to learn that isn't covered by the manual?

> My opinion (expressed with gratitude for the efforts of developers and
> documenters of asdf) is that Chapter 5 talks all around the thing that I
> most want to know, viz. "What does defsystem do?"
>
It builds an object of class SYSTEM that describes your system
and can be used by other methods. Semantically, it does nothing.
Syntactically, it translates from human-friendly syntax to
computer-friendly structures, with a few trivial normalizations
along the way.

> After a couple of examples, probably the manual should then contain an
> informal description of defsystem semantics. I know, of course, that it
> means to allow one to define a "system." But how? What is the strategy, and
> how do the bits of the defsystem form implement that strategy?
>
Defsystem has no strategy whatsoever.
It just recurses through the syntax to build a DAG
as obviously specified by the user.
All the "logic" is in OPERATE and the TRAVERSE infrastructure it uses.
See notably section 2 of our ILC2010 paper:
	http://common-lisp.net/project/asdf/ilc2010draft.pdf

[ François-René ÐVB Rideau | Reflection&Cybernethics | http://fare.tunes.org ]
God gave me brains so that I use it, and appreciate his work with the eyes
of a critic and a connoisseur; not so that I behave like a fool, and
believe the twaddles of the first come prophets and priests.
		— Faré