Reorganize imports and exports of `grammar.rkt`

parser-tools/private-yacc/grammar.rkt

@@ -6,31 +6,6 @@
          yaragg/parser-tools/private-yacc/yacc-helper
          racket/contract)
 
-;; Each production has a unique index 0 <= index <= number of productions
-(struct prod (lhs rhs index prec action) #:mutable)
-
-;; The dot-pos field is the index of the element in the rhs
-;; of prod that the dot immediately precedes.
-;; Thus 0 <= dot-pos <= (vector-length rhs).
-(struct item (prod dot-pos) #:transparent)
-  
-;; gram-sym = (union term? non-term?)
-;; Each term has a unique index 0 <= index < number of terms
-;; Each non-term has a unique index 0 <= index < number of non-terms  
-(struct term (sym index prec) #:mutable)
-(struct non-term (sym index) #:mutable)
-
-;; a precedence declaration.
-(struct prec (num assoc) #:transparent)
-  
-(provide/contract
- [item (prod? (or/c #f natural-number/c) . -> . item?)]
- [term (symbol? (or/c #f natural-number/c) (or/c prec? #f) . -> . term?)]
- [non-term (symbol? (or/c #f natural-number/c) . -> . non-term?)]
- [prec (natural-number/c (or/c 'left 'right 'nonassoc) . -> . prec?)]
- [prod (non-term? (vectorof (or/c non-term? term?))
-                  (or/c #f natural-number/c) (or/c #f prec?) syntax? . -> . prod?)])
-  
 (provide
  ;; Things that work on items
  start-item? item-prod item->string 
@@ -47,8 +22,32 @@
  grammar%
    
  ;; Things that work on productions
- prod-index prod-prec prod-rhs prod-lhs prod-action)
+ prod-index prod-prec prod-rhs prod-lhs prod-action
 
+ (contract-out
+  [item (prod? (or/c #f natural-number/c) . -> . item?)]
+  [term (symbol? (or/c #f natural-number/c) (or/c prec? #f) . -> . term?)]
+  [non-term (symbol? (or/c #f natural-number/c) . -> . non-term?)]
+  [prec (natural-number/c (or/c 'left 'right 'nonassoc) . -> . prec?)]
+  [prod (non-term? (vectorof (or/c non-term? term?))
+                   (or/c #f natural-number/c) (or/c #f prec?) syntax? . -> . prod?)]))
+  
+;; Each production has a unique index 0 <= index <= number of productions
+(struct prod (lhs rhs index prec action) #:mutable)
+
+;; The dot-pos field is the index of the element in the rhs
+;; of prod that the dot immediately precedes.
+;; Thus 0 <= dot-pos <= (vector-length rhs).
+(struct item (prod dot-pos) #:transparent)
+  
+;; gram-sym = (union term? non-term?)
+;; Each term has a unique index 0 <= index < number of terms
+;; Each non-term has a unique index 0 <= index < number of non-terms  
+(struct term (sym index prec) #:mutable)
+(struct non-term (sym index) #:mutable)
+
+;; a precedence declaration.
+(struct prec (num assoc) #:transparent)
   
 ;;---------------------- LR items --------------------------