Define Rust bindings (#2053)

Close #2046.

engine/src/fight.scm

@@ -1,8 +1,9 @@
-(import (scheme base) (stak base))
+(import (scheme base) (stak rust))
 
-(define make-person (primitive 1000))
-(define person-throw-pie (primitive 1001))
-(define person-wasted (primitive 1002))
+(define-rust
+  make-person
+  person-throw-pie
+  person-wasted)
 
 (define me (make-person 4 0.2))
 (define you (make-person 2 0.6))

prelude.scm

@@ -3354,3 +3354,24 @@
                   '())))))))
 
     (define environment list)))
+
+(define-library (stak rust)
+  (export define-rust)
+
+  (import
+    (only (stak base) primitive)
+    (scheme base))
+
+  (begin
+    (define-syntax define-rust
+      (syntax-rules ()
+        ((_ "count" index name1 name2 ...)
+          (begin
+            (define name1 (primitive index))
+            (define-rust "count" (+ index 1) name2 ...)))
+
+        ((_ "count" index)
+          #f)
+
+        ((_ name1 name2 ...)
+          (define-rust "count" 1000 name1 name2 ...))))))