compat: srfi-43: Adjust for Mes.

* gash/compat/srfi-43.scm (shared-shims): New macro.
[if-guile-version-below (2 0 10)]: Use it.
[mes]: Likewise.

gash/compat/srfi-43.scm

@@ -26,16 +26,26 @@
 ;;;
 ;;; Code:
 
+(define-macro (shared-shims)
+  '(begin
+     (export vector-empty?
+             vector-every)
+
+     (define (vector-empty? vec)
+       (zero? (vector-length vec)))
+
+     ;; We only need the single vector version.
+     (define (vector-every pred? vec)
+       (let loop ((i 0) (value #t))
+         (if (< i (vector-length vec))
+             (and value (loop (1+ i) (pred? (vector-ref vec i))))
+             value)))))
+
 (if-guile-version-below (2 0 10)
-  (begin
-    (define-public (vector-empty? vec)
-      (zero? (vector-length vec)))
-    ;; We only need the single vector version.
-    (define-public (vector-every pred? vec)
-      (let loop ((i 0) (value #t))
-        (if (< i (vector-length vec))
-            (and value (loop (1+ i) (pred? (vector-ref vec i))))
-            value))))
+  (shared-shims)
   (begin
     (use-modules (srfi srfi-43))
     (re-export vector-empty? vector-every)))
+
+(when-mes
+  (shared-shims))