cannot import procedure from one egg during macro expansion in another egg.

[Alan Post]

I have two eggs, m0 and m1.

m0 defines a single procedure, f0.

m1 contains an ir-macro make-f1, which defines the procedure f1. It calls m0#f0 during macro expansion.

I get the following error during macro expansion, claiming f1 is undefined:

Error: during expansion of (make-f1 ...) - unbound variable: f0

I believe f0 is bound, and that this expansion should succeed. See attached files.

my csc version:

--(>:)-- csc -V
(c) 2008-2013, The Chicken Team
(c) 2000-2007, Felix L. Winkelmann
Version 4.8.0.5 (stability/4.8.0) (rev f60b2b6)
openbsd-unix-gnu-x86 [ manyargs dload ptables ]
compiled 2013-12-10 on celia.c0redump.org (OpenBSD)

[Alan Post]

m0.scm

[Alan Post]

m1.scm

[Alan Post]

doit

[Alan Post]

main.scm

[Alan Post]

evhan, on IRC, found the appropriate invocation:

(begin-for-syntax

(require-library m0))

(import-for-syntax m0)

Is this still a bug? Since there is a workaround, I'm dropping the priority.

[evhan]

I think the important difference in ​the working paste is actually just having (import scheme) before the begin-for-syntax form. As long as that's true, any other permutation of the imports works:

(import-for-syntax scheme)
(import-for-syntax chicken)
(import scheme)
(begin-for-syntax (use m0))
(import chicken)
;; ... whatever else ...

This is because the scheme namespace is the one that provides begin-for-syntax, so without it the begin-for-syntax isn't expanded and m0 isn't loaded in m1 at expansion time (making f0 a run-of-the-mill unbound variable). I'd call this a gotcha rather than a bug, though maybe a warning for forms that are probably meant to be syntax like this (such as the {import,require,use}[-for-syntax] family) would be helpful?

[evhan]

Closing as invalid after looking into this again. The current behaviour is as expected, just a bit obscured by the macrology.