diff --git a/utils-tests.rkt b/utils-tests.rkt
index 86e3b48..d756bd4 100644
--- a/utils-tests.rkt
+++ b/utils-tests.rkt
@@ -37,4 +37,7 @@
 (test-case "Variable mapping and Org-mode"
   (check-equal? (any->string 'a) "a")
   (check-equal? (any->string '(a 1 (x y))) "(a 1 (x y))")
-  (check-equal? (any->string "hello") "hello"))
+  (check-equal? (any->string "hello") "hello")
+  (let ([mp (variable-mapping-stringify #hash((a . (and a b)) (b . (not b))))])
+    (check-equal? (hash-ref mp 'a) "(and a b)")
+    (check-equal? (hash-ref mp 'b) "(not b)")))
diff --git a/utils.rkt b/utils.rkt
index 45ebcf7..d0435d0 100644
--- a/utils.rkt
+++ b/utils.rkt
@@ -15,7 +15,9 @@
                [hash-pred (->* (hash?)
                                (#:key-pred any/c #:val-pred any/c)
                                boolean?)]
-               [any->string (-> any/c string?)])
+               [any->string (-> any/c string?)]
+               [variable-mapping-stringify (-> variable-mapping? string-variable-mapping?)]
+               [string-variable-mapping? (-> any/c boolean?)])
  ;; Syntax
  auto-hash-ref/explicit auto-hash-ref/:)
 
@@ -162,3 +164,11 @@
 ;;; Converts any value to string.
 (define (any->string x)
   (with-output-to-string (λ () (display x))))
+
+;;; A string variable mapping is a mapping from variables to strings.
+(define (string-variable-mapping? dict) (hash-pred dict #:key-pred symbol? #:val-pred string?))
+
+;;; Converts all the values of a variable mapping to string.
+(define (variable-mapping-stringify ht)
+  (make-hash (hash-map ht (λ (key val)
+                            (cons key (any->string val))))))