add more operations on number snips

gui-lib/framework/main.rkt

@@ -193,22 +193,38 @@
 
  (proc-doc/names
   number-snip:make-repeating-decimal-snip
-  (real? boolean? . -> . (is-a?/c snip%))
+  (-> real? boolean? number-snip:is-number-snip?)
   (num show-prefix?)
-  @{Makes a number snip that shows the decimal expansion for @racket[number].
+  @{Makes a @tech{number snip} that shows the decimal expansion for @racket[number].
     The boolean indicates if a @litchar{#e} prefix appears on the number.
     
     See also @racket[number-snip:make-fraction-snip].})
 
  (proc-doc/names
   number-snip:make-fraction-snip
-  (real? boolean? . -> . (is-a?/c snip%))
+  (-> real? boolean? number-snip:is-number-snip?)
   (num show-prefix-in-decimal-view?)
-  @{Makes a number snip that shows a fractional view of @racket[number].
+  @{Makes a @tech{number snip} that shows a fractional view of @racket[number].
     The boolean indicates if a @litchar{#e} prefix appears on the number, when
     shown in the decimal state.
     
     See also @racket[number-snip:make-repeating-decimal-snip].})
+
+ (proc-doc/names
+  number-snip:is-number-snip?
+  (-> any/c boolean?)
+  (v)
+  @{Determines if @racket[v] is a @deftech{number snip}, i.e., created
+                  by @racket[number-snip:make-fraction-snip]
+                  or @racket[number-snip:make-repeating-decimal-snip].
+
+ All values that answer @racket[#t] to this predicate are also @racket[snip%]s.})
+
+ (proc-doc/names
+  number-snip:get-number
+  (-> number-snip:is-number-snip? real?)
+  (ns)
+  @{Returns the number that this @tech{number snip} displays.})
  
  (thing-doc
   comment-box:snipclass

gui-lib/framework/private/number-snip.rkt

@@ -92,6 +92,8 @@
                        (send number-snip get-text 0 1)]
                       [else default]))])))
 
+  (define (get-number s) (send s get-number))
+
   (define (is-number-snip? x) (is-a? x number-snip%))
   (define number-snip%
     (class* snip% (readable-snip<%> number-snip-convertible<%>)

gui-lib/framework/private/sig.rkt

@@ -9,9 +9,11 @@
     (snip-class%))
   (define-signature number-snip^ extends number-snip-class^
     (make-repeating-decimal-snip
-     make-fraction-snip))
+     make-fraction-snip
+     is-number-snip?
+     get-number))
   (define-signature number-snip/int^ extends number-snip^
-    (is-number-snip?))
+    ())
   
   (define-signature comment-box-class^
     (snip%))

gui-test/framework/tests/README

@@ -66,7 +66,7 @@ signal failures when there aren't any.
   | make sure that mred:the-frame-group records frames correctly.
   | fake user input expected.
 
-- number snip: |# number-snip.rkt #|
+- number snip: number-snip.rkt  -- now runs directly via raco test
 
   | some tests for the number-snip% class
 

gui-test/framework/tests/number-snip.rkt

@@ -1,22 +1,27 @@
 #lang racket/base
-(require "test-suite-utils.rkt")
+(require "test-suite-utils.rkt"
+         racket/contract
+         framework
+         file/convertible
+         rackunit)
 
-(test
- 'number-snip-convert-text
- (λ (x) (or (equal? "1/2" x) (equal? "0.5" x)))
- (lambda ()
-   (queue-sexp-to-mred
-    `((dynamic-require 'file/convertible 'convert)
+(check-true
+ (let ()
+   (define x
+     (convert
       (number-snip:make-fraction-snip 1/2 #f)
       'text
-      #f))))
+      #f))
+   (or (equal? "1/2" x) (equal? "0.5" x))))
 
-(test
- 'number-snip-convert-png
- bytes?
- (lambda ()
-   (queue-sexp-to-mred
-    `((dynamic-require 'file/convertible 'convert)
-      (number-snip:make-fraction-snip 1/2 #f)
-      'png-bytes
-      #f))))
+
+(check-true
+ (bytes?
+  (convert
+   (number-snip:make-fraction-snip 1/2 #f)
+   'png-bytes
+   #f)))
+
+(check-true (number-snip:is-number-snip? (number-snip:make-fraction-snip 3/2 #t)))
+(check-false (number-snip:is-number-snip? 3/2))
+(check-equal? 3/2 (number-snip:get-number (number-snip:make-fraction-snip 3/2 #t)))