Display help in browser tool

basis/help/help-docs.factor

@@ -129,12 +129,17 @@ HELP: $title
 { $values { "topic" "a help article name or a word" } }
 { $description "Prints a help article's title, or a word's " { $link summary } ", depending on the type of " { $snippet "topic" } "." } ;
 
+HELP: print-topic
+{ $values { "topic" "an article name or a word" } }
+{ $description
+    "Displays a help topic on " { $link output-stream } "."
+} ;
+
 HELP: help
 { $values { "topic" "an article name or a word" } }
 { $description
-    "Displays a help article or documentation associated to a word on " { $link output-stream } "."
+    "Displays a help topic."
 } ;
-
 HELP: about
 { $values { "vocab" "a vocabulary specifier" } }
 { $description

basis/help/help.factor

@@ -89,10 +89,17 @@ M: word set-article-parent swap "help-parent" set-word-prop ;
         ] with-nesting
     ] with-style nl ;
 
-: help ( topic -- )
+: print-topic ( topic -- )
     last-element off dup $title
     article-content print-content nl ;
 
+SYMBOL: help-hook
+
+help-hook global [ [ print-topic ] or ] change-at
+
+: help ( topic -- )
+    help-hook get call ;
+
 : about ( vocab -- )
     dup require
     dup vocab [ ] [

basis/ui/tools/browser/browser.factor

@@ -4,17 +4,17 @@ USING: debugger ui.tools.workspace help help.topics kernel
 models models.history ui.commands ui.gadgets ui.gadgets.panes
 ui.gadgets.scrollers ui.gadgets.tracks ui.gestures
 ui.gadgets.buttons compiler.units assocs words vocabs
-accessors ;
+accessors fry combinators.short-circuit ;
 IN: ui.tools.browser
 
 TUPLE: browser-gadget < track pane history ;
 
 : show-help ( link help -- )
-    dup history>> add-history
-    >r >link r> history>> set-model ;
+    history>> dup add-history
+    [ >link ] dip set-model ;
 
 : <help-pane> ( browser-gadget -- gadget )
-    history>> [ [ help ] curry try ] <pane-control> ;
+    history>> [ '[ _ print-topic ] try ] <pane-control> ;
 
 : init-history ( browser-gadget -- )
     "handbook" >link <history> >>history drop ;
@@ -22,7 +22,7 @@ TUPLE: browser-gadget < track pane history ;
 : <browser-gadget> ( -- gadget )
     { 0 1 } browser-gadget new-track
         dup init-history
-        dup <toolbar> f track-add
+        add-toolbar
         dup <help-pane> >>pane
         dup pane>> <scroller> 1 track-add ;
 
@@ -38,10 +38,11 @@ M: browser-gadget ungraft*
     [ call-next-method ] [ remove-definition-observer ] bi ;
 
 : showing-definition? ( defspec assoc -- ? )
-    [ key? ] 2keep
-    [ >r dup word-link? [ name>> ] when r> key? ] 2keep
-    >r dup vocab-link? [ vocab ] when r> key?
-    or or ;
+    {
+        [ key? ]
+        [ [ dup word-link? [ name>> ] when ] dip key? ]
+        [ [ dup vocab-link? [ vocab ] when ] dip key? ]
+    } 2|| ;
 
 M: browser-gadget definitions-changed ( assoc browser -- )
     history>>