> Program-vicinity is typically used to load pieces of programs at what
> in Common-Lisp is called compile-time.  But program-vicinity is also
> used at run-time for locating the software license or help text, for
> instance.

That's not what srfi-59.html says:
   For a compiled system (with multiple files) this would be the
   directory where the object or executable files are.

> We would like to be able to call
> program-vicinity at any point in the code and have it return the same
> value as a top-level-captured vicinity.  But to have it evaluated
> during the load would require it be a read-syntax, wouldn't it?

It can be regular syntax *iff* the Scheme reader annotates the
resulting forms with line-number information, in some way or other.
Some Schemes do - at least Chez Scheme, PLT Scheme, and Kawa.
Any Scheme that can provide error diagnostics with a line-number
needs some way of doing this.

> Must source-vicinity be distinct from program-vcinity?

Perhaps not, depending on how it is defined.

Consider:
f.scm:
(define (f) (source-vicinity))

g.scm:
(define v (f))

Top-level:
(load "f.scm")
(load "g.scm")

What is the value of v?  It should return "f.scm".
I do believe this is useful, for diagnostics.

If you replace source-vicinity by program-vicinity, and the
latter is defined as "Returns the vicinity of the currently
loading Scheme code" then the result would be "g.scm".
Is that useful?  I don't know.

If only one of these results is useful, then you can combine
them.
--
	--Per Bothner
xxxxxx@bothner.com   http://per.bothner.com/