From e96d9460fd58ccf4ac8a044bda269b241cf4b9ef Mon Sep 17 00:00:00 2001
From: Robby Findler <robby@racket-lang.org>
Date: Sat, 29 Jan 2011 12:26:59 -0600
Subject: [PATCH] added a color:text method get-token-range and then used that
 to improve how f1 in drracket works   Please include this commit on the
 release branch

original commit: 4090eabacb8d7b32900b4df18da06f14f1def40f
---
 collects/framework/private/color.rkt       | 18 ++++++++++++++----
 collects/scribblings/framework/color.scrbl | 12 +++++++++++-
 2 files changed, 25 insertions(+), 5 deletions(-)

diff --git a/collects/framework/private/color.rkt b/collects/framework/private/color.rkt
index f7be4ce5..08ef4f5e 100644
--- a/collects/framework/private/color.rkt
+++ b/collects/framework/private/color.rkt
@@ -817,16 +817,26 @@ added get-regions
     
     ;; Determines whether a position is a 'comment, 'string, etc.
     (define/public (classify-position position)
+      (define tokens (get-tokens-at-position 'classify-position position))
+      (and tokens
+           (let ([root-data (send tokens get-root-data)])
+             (and root-data
+                  (data-type root-data)))))
+
+    (define/public (get-token-range position)
+      (define tokens (get-tokens-at-position 'get-token-range position))
+      (values (and tokens (send tokens get-root-start-position))
+              (and tokens (send tokens get-root-end-position))))
+
+    (define/private (get-tokens-at-position who position)
       (when stopped?
-        (error 'classify-position "called on a color:text<%> whose colorer is stopped."))
+        (error who "called on a color:text<%> whose colorer is stopped."))
       (let ([ls (find-ls position)])
         (and ls
              (let ([tokens (lexer-state-tokens ls)])
                (tokenize-to-pos ls position)
                (send tokens search! (- position (lexer-state-start-pos ls)))
-               (let ([root-data (send tokens get-root-data)])
-                 (and root-data
-                      (data-type root-data)))))))
+               tokens))))
     
     (define/private (tokenize-to-pos ls position)
       (when (and (not (lexer-state-up-to-date? ls)) 
diff --git a/collects/scribblings/framework/color.scrbl b/collects/scribblings/framework/color.scrbl
index 979155fa..2dd561e6 100644
--- a/collects/scribblings/framework/color.scrbl
+++ b/collects/scribblings/framework/color.scrbl
@@ -212,7 +212,7 @@
     right kind.  If @scheme[flash?] is true, the matching open parenthesis will be
     flashed.
   }
-  @defmethod*[(((classify-position (position natural-number?)) symbol?))]{
+  @defmethod*[(((classify-position (position exact-nonnegative-integer?)) symbol?))]{
 
 
     Return a symbol for the lexer-determined token type for the token that
@@ -221,6 +221,16 @@
     Must only be called while the tokenizer is started.
   }
   
+  @defmethod[(get-token-range [position exact-nonnegative-integer?]) 
+             (values (or/c #f exact-nonnegative-integer?)
+                     (or/c #f exact-nonnegative-integer?))]{
+    
+    Returns the range of the token surrounding @racket[position], if there is a token there.
+    
+    This method must be called only when the tokenizer is started.
+    
+  }
+  
   @defmethod[#:mode augment (on-lexer-valid [valid? boolean?]) any]{
     This method is an observer for when the lexer is working.
     It is called when the lexer's state changes from valid to invalid (and back).