I'd like to be able to get source location information from behind two or more
layers of macros.
I have a macro, call it mk-data, whose job it is to make an internal data
structure. Among other things, it records a srcloc for later tracking. In
another module, I have another macro whose job it is to specialize mk-data and
present a simpler interface.
Unfortunately, the srcloc that gets stored ends up being the location of the
simplifying macro. Not what I want. I need to somehow forward the srcloc of its
use-location. Example follows:
a.rkt:
#lang racket
(provide mk-data getloc)
(struct data-internal
(name x y srcloc)
#:guard (λ (n x y srcloc struct-name)
(unless (real? x)
(raise-argument-error 'data-internal "real?" x))
(unless (real? y)
(raise-argument-error 'data-internal "real?" y))
(values n x y srcloc)))
(define-syntax (mk-data stx)
(syntax-case stx ()
[(_ name x y)
#`(data-internal name x y (srcloc #,(syntax-source stx)
#,(syntax-line stx)
#,(syntax-column stx)
#,(syntax-position stx)
#,(syntax-span stx)))]))
(define (getloc d) (srcloc->string (data-internal-srcloc d)))
b.rkt:
#lang racket
(provide simple-data)
(require "a.rkt")
(define-syntax (simple-data stx)
(syntax-case stx ()
[(_ name x)
#'(mk-data 'name x 42)]))
c.rkt:
#lang racket
(require "a.rkt" "b.rkt")
(getloc (simple-data unlucky 262))
I want the result in c.rkt to be "c.rkt:3:9" or so, rather than "b.rkt:7:7".
I realize I could probably make the simple-data macro in b.rkt a bit more
sophisticated to help matters, but I'm really resisting doing so. There are
going to be a lot of macros like simple-data, and some of them may be written
by users, so I'd like to make it as simple as possible to make new ones. I'd
rather change mk-data, even if it means making it significantly more complex.
What's the best way to accomplish this?
--
You received this message because you are subscribed to the Google Groups
"Racket Users" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to racket-users+unsubscr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.
