utils: Add list-sets->list-strings.

scribblings/utils.scrbl

@@ -1,6 +1,7 @@
 #lang scribble/manual
 @(require scribble/example racket/sandbox
-	  (for-label typed/racket/base graph "../utils.rkt"))
+	  (for-label typed/racket/base graph "../utils.rkt"
+	  	     (only-in racket/set set)))
 
 @title[#:tag "utils"]{dds/utils: Various Utilities}
 
@@ -232,6 +233,15 @@ Useful for removing the parentheses in string representations of lists.
 (drop-first-last "(a b)")
 ]}
 
+@defproc[(list-sets->list-strings (lst (Listof (Setof Any)))) (Listof String)]{
+
+Converts a list of sets of symbols to a list of strings containing
+those symbols.
+
+@examples[#:eval utils-evaluator
+(list-sets->list-strings (list (set 'x 'y) (set 'z) (set) (set 't)))
+]}
+
 @section{Additional graph utilities}
 
 @section{Pretty printing}

utils-untyped.rkt

@@ -10,8 +10,7 @@
 
 (provide
  ;; Functions
- (contract-out [list-sets->list-strings (-> (listof (set/c any/c)) (listof string?))]
-               [pretty-print-set-sets (-> (set/c (set/c symbol?) #:kind 'dont-care) string?)]
+ (contract-out [pretty-print-set-sets (-> (set/c (set/c symbol?) #:kind 'dont-care) string?)]
                [update-vertices/unweighted (-> graph? (-> any/c any/c) graph?)]
                [update-graph (->* (graph?)
                                   (#:v-func (-> any/c any/c)

utils.rkt

@@ -10,6 +10,7 @@
          any->string stringify-variable-mapping string->any map-sexp
          read-org-sexp unorg unstringify-pairs
          read-org-variable-mapping unorgv read-symbol-list drop-first-last
+         list-sets->list-strings
          ;; Syntax
          auto-hash-ref/explicit auto-hash-ref/:)
 
@@ -270,3 +271,15 @@
 (module+ test
   (test-case "drop-first-last"
     (check-equal? (drop-first-last "(a b)") "a b")))
+
+(: list-sets->list-strings (-> (Listof (Setof Any)) (Listof String)))
+(define (list-sets->list-strings lst)
+  (map (multi-compose drop-first-last
+                      any->string
+                      (λ ([x : (Setof Any)])
+                        (set->list x))) lst))
+
+(module+ test
+  (test-case "list-sets->list-strings"
+    (check-equal? (list-sets->list-strings (list (set 'x 'y) (set 'z) (set) (set 't)))
+                  '("y x" "z" "" "t"))))