My experiments with side-effects and separate compilation

4 files changed, 41 insertions, 0 deletions

diff --git a/scheme/experimental/define+.sls b/scheme/experimental/define+.sls
new file mode 100644
index 0000000..2e0b21b
--- /dev/null
+++ b/scheme/experimental/define+.sls
@@ -0,0 +1,23 @@
+#!r6rs
+(library (experimental define+)
+(export define-registered define+)
+(import (rnrs) (for (experimental registry) expand))
+
+;; save the content of the expand-time registry into a runtime definition
+(define-syntax define-registered
+  (lambda (x)
+    (syntax-case x ()
+        ((define-registered names)
+         #`(define names '#,(registry))))))
+
+(define-syntax define+
+  (lambda (x)
+    (syntax-case x ()
+      ((define+ name value)
+       #'(begin
+           ;; dirty trick to get an expand time side effect
+           (define-syntax dummy (begin (register #'name) (lambda (x) #f)))
+           ;; the real definition
+           (define name value))))))
+
+)
diff --git a/scheme/experimental/defines.sls b/scheme/experimental/defines.sls
new file mode 100644
index 0000000..4dc65cd
--- /dev/null
+++ b/scheme/experimental/defines.sls
@@ -0,0 +1,11 @@
+#!r6rs
+(library (experimental defines)
+(export a b visit-defines)
+(import (rnrs) (experimental define+))
+
+(define-syntax visit-defines
+  (lambda (x) "visited"))
+(define+ a 1)
+(define+ b 2)
+)
+
diff --git a/scheme/experimental/registry.sls b/scheme/experimental/registry.sls
index c8f06c1..e34c027 100644
--- a/scheme/experimental/registry.sls
+++ b/scheme/experimental/registry.sls
@@ -12,4 +12,6 @@
   (printf "registering ~a\n" id)
   (set! _registry (append _registry (list id)))
   _registry)
+
+(display "registry instantiated\n")
 )
diff --git a/scheme/experimental/use-defines.ss b/scheme/experimental/use-defines.ss
new file mode 100644
index 0000000..7d65148
--- /dev/null
+++ b/scheme/experimental/use-defines.ss
@@ -0,0 +1,5 @@
+(import (rnrs) (experimental define+) (experimental defines))
+(visit-defines)
+(define-registered names)
+(display names)
+(display (list a b));; just to use the names defined in defines