exported by the environment. Try
> (environment-symbols (environment '(rnrs)))
- Added an internal export mechanism so that identifiers can be
exported from within a library. The syntax is the same:
(export export-spec* ...)
when appears in a library's top level, adds the export specs to
the set of exported identifiers. So, one can do:
(library (A)
(export)
(import (ikarus))
(export a)
(define a 17))
When appearing in non-library definition context, the export form
is ignored.
indices (r6rs requirement).
- file-options are now represented as enum-sets (r6rs requirement)
- odd?, even?, lcm, remainder, etc., now accept inexact integers.
- (optimize-level [0,1,2]) and ikarus -O[0,1,2]
where -O0 = no optimizations
-O1 = using old optimizer
-O2 = using the new cp0 optimizer
defaults to -O1 for now.
- (cp0-size-limit n) which is the limit of the residual size for
each inlining attempt
- (cp0-effort-limit n) which is the limit on the effort expended
for each inlining attempt
- Rewrote the syntax-match macro to make use of the same technology
used in syntax-case itself resulting in reduced code size.
- Added (system-value <symbol>) which returns the system value.
E.g., (system-value 'car) => #<procedure car>
This is pretty much the same as
(eval <symbol> (environment '(ikarus)))
except that it does not involve compiling the expression or
consulting the library/expander systems.
- Fixed the fasl loader to make it understand complex numbers.
top-marked wrapped syntax objects were incorrectly combined.
E.g., it used to be that:
(syntax-case (datum->syntax #'foo #'(x y)) ()
[(x y) 'shouldntmatch] [_ 'ok])
yields shouldntmatch; it's now ok.
- We can now redefine imported identifiers.
- We can now use let-syntax, letrec-syntax, and modules at
top-level.
Hand-wavey Repl Semantics:
- Imported identifiers mean what they meant previously. In
particular, you cannot set! imported identifiers.
- An imported identifier may be redefined using define. Once
something is defined at the top-level, a specific location for it
is created, and all definitions, references, and set!s to that
variable go through the top-level location.
- Re-importing an identifier shadows the top-level location.
- Redefining re-exposes the top-level location.
- and do on.
- A reference to an unbound variable also fabricates a top-level
location for that variable.
Let's see how this goes.
(Note from Kent, extracted from chez scheme release notes, follows)
This always worked:
(let ()
(define-syntax from
(syntax-rules ()
[(_ m v) (let () (import m) v)]))
(module a (x) (define x 'x-of-a))
(from a x))
Didn't work before this change:
(let ()
(define-syntax x-from-a
(syntax-rules ()
[(_) (let () (import a) x)]))
(module a (x) (define x 'x-of-a))
(x-from-a))