start `begin-label` experiment

beautiful-racket-lib/br/begin-label.rkt

@@ -0,0 +1,27 @@
+#lang br
+(require rackunit)
+(provide (all-defined-out))
+
+(define (syntax->source stx)
+  ;; reconstitute the source string by using srclocs
+  ;; magic goes here
+    stx)
+
+(define-macro (begin-label LABEL . EXPRS)
+  #'(begin
+      (define LABEL (syntax->source #'EXPRS))
+      (provide LABEL)
+      (begin . EXPRS)))
+
+(begin-label
+  zing
+  (define (f x)
+    (+ x x))
+  
+  (define (g x)
+    (* x x)))
+
+(display zing)
+
+(check-equal? (f 5) 10)
+#;(check-equal? (g 5) 25)