* module/ice-9/psyntax.scm (quote-syntax): New core form. Usually the
expander will unwrap all syntax objects from the input term. However
sometimes you want to preserve a syntax object, as a datum. That's
when you want quote-syntax.
* module/ice-9/psyntax-pp.scm: Regenerate.
* module/ice-9/local-eval.scm (identifier-syntax-from-box): Use
quote-syntax instead of our datum->syntax trick, which relied on
psyntax's special treatment of the top mark.
* module/ice-9/psyntax.scm (binding-type): Update the header comment
to mention the new 'ellipsis' binding type.
(macros-only-env): Preserve ellipsis bindings.
(ellipsis?): Add 'r' and 'mod' as arguments. Search the lexical
environment for an ellipsis binding, and use it.
(gen-syntax): Adapt to the additional arguments of 'ellipsis?'.
(with-ellipsis): New core syntax.
(convert-pattern): Add unary 'ellipsis?' procedure as an argument.
(gen-clause): Adapt to the additional arguments of 'ellipsis?'.
Pass unary 'ellipsis?' procedure to 'convert-pattern'.
(syntax-case): Adapt to the additional arguments of 'ellipsis?'.
(syntax-local-binding): Support new 'ellipsis' binding type.
(syntax-rules): Add support for a custom ellipsis identifier as
the first operand, as per R7RS. Collect common code within new
local procedure 'expand-syntax-rules'.
* module/ice-9/psyntax-pp.scm: Regenerate.
* module/ice-9/local-eval.scm (analyze-identifiers): Add support for
'ellipsis' binding type.
* doc/ref/api-macros.texi (Syntax Rules): Add docs for R7RS custom
ellipsis syntax. Use @dots{}.
(Syntax Case): Add docs for 'with-ellipsis'. Use @dots{}.
(Syntax Transformer Helpers): Update to include new 'ellipsis'
binding type.
* test-suite/tests/syntax.test: Add tests.
* module/ice-9/local-eval.scm (local-wrap): Fix the (module? e) case, to
reference the expression 'x' instead of the non-existent variable
'exp', as was previously done. Also use quasisyntax instead of
quasiquote, so that the introduced 'lambda' is an identifier instead
of a bare symbol, so that this will work in modules that have rebound
'lambda' to something else.
* test-suite/tests/eval.test (local-eval): Make sure to test both
'local-eval' and 'local-compile' when the specified environment is a
module.
* module/ice-9/local-eval.scm: New module (ice-9 local-eval) which
exports `the-environment', `local-eval', and `local-compile'.
* libguile/debug.c (scm_local_eval): New C function that calls the
Scheme implementation of `local-eval' in (ice-9 local-eval).
* libguile/debug.h (scm_local_eval): Add prototype.
* doc/ref/api-evaluation.texi (Local Evaluation): Add documentation.
* test-suite/tests/eval.test (local evaluation): Add tests.
* test-suite/standalone/test-loose-ends.c (test_scm_local_eval):
Add test.
* module/Makefile.am: Add ice-9/local-eval.scm.
Based on a patch by Mark H Weaver <mhw@netris.org>.