Index: art/syntax/bubble-generator.tcl
==================================================================
--- art/syntax/bubble-generator.tcl
+++ art/syntax/bubble-generator.tcl
@@ -39,10 +39,25 @@
 set RADIUS 9                      ;# default turn radius
 set HSEP 17                       ;# horizontal separation
 set VSEP 9                        ;# vertical separation
 set DPI 80                       ;# dots per inch
 
+# Move all widgets with $tag and/or $tag-txt
+#
+proc move_glyphs {tag dx dy} {
+  .c move $tag $dx $dy
+  .c move $tag-txt $dx $dy
+}
+
+# Change all widgets tagged with $old to $new or with $old-txt to $new-txt
+#
+proc retag {old new} {
+  .c addtag $new withtag $old
+  .c addtag $new-txt withtag $old-txt
+  .c dtag $old
+  .c dtag $old-txt
+}
 
 # Draw a right-hand turn around.  Approximately a ")"
 #
 proc draw_right_turnback {tag x y0 y1} {
   global RADIUS
@@ -128,11 +143,11 @@
     set istoken 0
   } else {
     set font $::font1
     set istoken 1
   }
-  set id1 [.c create text 0 0 -anchor c -text $txt -font $font -tags $tag]
+  set id1 [.c create text 0 0 -anchor c -text $txt -font $font -tags $tag-txt]
   foreach {x0 y0 x1 y1} [.c bbox $id1] break
   set h [expr {$y1-$y0+2}]
   set rad [expr {($h+1)/2}]
   set top [expr {$y0-2}]
   set btm [expr {$y1}]
@@ -142,27 +157,25 @@
   set right [expr {$x1-$fudge}]
   if {$left>$right} {
     set left [expr {($x0+$x1)/2}]
     set right $left
   }
-  set tag2 x$tagcnt-box
-  set tags [list $tag $tag2]
   if {$istoken} {
     .c create arc [expr {$left-$rad}] $top [expr {$left+$rad}] $btm \
-         -width 2 -start 90 -extent 180 -style arc -tags $tags
+         -width 2 -start 90 -extent 180 -style arc -tags $tag
     .c create arc [expr {$right-$rad}] $top [expr {$right+$rad}] $btm \
-         -width 2 -start -90 -extent 180 -style arc -tags $tags
+         -width 2 -start -90 -extent 180 -style arc -tags $tag
     if {$left<$right} {
-      .c create line $left $top $right $top -width 2 -tags $tags
-      .c create line $left $btm $right $btm -width 2 -tags $tags
+      .c create line $left $top $right $top -width 2 -tags $tag
+      .c create line $left $btm $right $btm -width 2 -tags $tag
     }
   } else {
-    .c create rect $left $top $right $btm -width 2 -tags $tags
+    .c create rect $left $top $right $btm -width 2 -tags $tag
   }
-  foreach {x0 y0 x1 y1} [.c bbox $tag2] break
+  foreach {x0 y0 x1 y1} [.c bbox $tag] break
   set width [expr {$x1-$x0}]
-  .c move $tag [expr {-$x0}] 0
+  move_glyphs $tag [expr {-$x0}] 0
 
   # Entry is always 0 0
   # Return:  TAG EXIT_X EXIT_Y
   #
   return [list $tag $width 0]
@@ -182,20 +195,19 @@
   foreach term $lx {
     set m [draw_diagram $term]
     foreach {t texx texy} $m break
     if {$exx>0} {
       set xn [expr {$exx+$sep}]
-      .c move $t $xn $exy
+      move_glyphs $t $xn $exy
       .c create line [expr {$exx-1}] $exy $xn $exy \
          -tags $tag -width 2 -arrow last
       set exx [expr {$xn+$texx}]
     } else {
       set exx $texx
     }
     set exy $texy
-    .c addtag $tag withtag $t
-    .c dtag $t $t
+    retag $t $tag
   }
   if {$exx==0} {	
     set exx [expr {$sep*2}]
     .c create line 0 0 $sep 0 -width 2 -tags $tag -arrow last
     .c create line $sep 0 $exx 0 -width 2 -tags $tag
@@ -224,19 +236,18 @@
     foreach {t texx texy} $m break
     foreach {tx0 ty0 tx1 ty1} [.c bbox $t] break
     set w [expr {$tx1-$tx0}]
     if {$exx>0} {
       set xn [expr {$exx+$sep}]
-      .c move $t $xn 0
+      move_glyphs $t $xn 0
       .c create line $exx $exy $xn $exy -tags $tag -width 2 -arrow first
       set exx [expr {$xn+$texx}]
     } else {
       set exx $texx
     }
     set exy $texy
-    .c addtag $tag withtag $t
-    .c dtag $t $t
+    retag $t $tag
   }
   if {$exx==0} {
     .c create line 0 0 $sep 0 -width 2 -tags $tag
     set exx $sep
   }
@@ -283,11 +294,11 @@
          .c create line $bypass_x $bypass_y $bypass_x $mid_y \
             -width 2 -tags $tag -arrow last
          .c create line $bypass_x $mid_y $bypass_x [expr {$back_y+$RADIUS}] \
              -tags $tag -width 2
       }
-      .c move $t $enter_x $enter_y
+      move_glyphs $t $enter_x $enter_y
       set e2 [expr {$exit_x + $sep}]
       .c create line $exit_x $exit_y $e2 $exit_y \
             -width 2 -tags $tag
       draw_right_turnback $tag $e2 $exit_y $back_y
       set e3 [expr {$enter_x-$sep}]
@@ -302,12 +313,11 @@
       .c create line $e3 $enter_y $enter_x $enter_y \
                  -arrow last -width 2 -tags $tag
       set exit_x [expr {$enter_x + $exx}]
       set exit_y [expr {$enter_y + $exy}]
     }
-    .c addtag $tag withtag $t
-    .c dtag $t $t
+    retag $t $tag
     set btm [lindex [.c bbox $tag] 3]
     incr i
   }
   if {$bypass} {
     set fwd_y [expr {$btm + $sep + 1}]
@@ -358,45 +368,43 @@
   set fw [expr {$fx1-$fx0}]
   foreach {bt bexx bexy} [draw_backwards_line $back] break
   foreach {bx0 by0 bx1 by1} [.c bbox $bt] break
   set bw [expr {$bx1-$bx0}]
   set dy [expr {$fy1 - $by0 + $vsep}]
-  .c move $bt 0 $dy
+  move_glyphs $bt 0 $dy
   set biny $dy
   set bexy [expr {$dy+$bexy}]
   set by0 [expr {$dy+$by0}]
   set by1 [expr {$dy+$by1}]
 
   if {$fw>$bw} {
     if {$fexx<$fw && $fexx>=$bw} {
       set dx [expr {($fexx-$bw)/2}]
-      .c move $bt $dx 0
+      move_glyphs $bt $dx 0
       set bexx [expr {$dx+$bexx}]
       .c create line 0 $biny $dx $biny -width 2 -tags $bt
       .c create line $bexx $bexy $fexx $bexy -width 2 -tags $bt -arrow first
       set mxx $fexx
     } else {
       set dx [expr {($fw-$bw)/2}]
-      .c move $bt $dx 0
+      move_glyphs $bt $dx 0
       set bexx [expr {$dx+$bexx}]
       .c create line 0 $biny $dx $biny -width 2 -tags $bt
       .c create line $bexx $bexy $fx1 $bexy -width 2 -tags $bt -arrow first
       set mxx $fexx
     }
   } elseif {$bw>$fw} {
     set dx [expr {($bw-$fw)/2}]
-    .c move $ft $dx 0
+    move_glyphs $ft $dx 0
     set fexx [expr {$dx+$fexx}]
     .c create line 0 0 $dx $fexy -width 2 -tags $ft -arrow last
     .c create line $fexx $fexy $bx1 $fexy -width 2 -tags $ft
     set mxx $bexx
   }
-  .c addtag $tag withtag $bt
-  .c addtag $tag withtag $ft
-  .c dtag $bt $bt
-  .c dtag $ft $ft
-  .c move $tag $sep 0
+  retag $bt $tag
+  retag $ft $tag
+  move_glyphs $tag $sep 0
   set mxx [expr {$mxx+$sep}]
   .c create line 0 0 $sep 0 -width 2 -tags $tag
   draw_left_turnback $tag $sep 0 $biny up
   draw_right_turnback $tag $mxx $fexy $bexy
   foreach {x0 y0 x1 y1} [.c bbox $tag] break
@@ -417,36 +425,34 @@
   set fw [expr {$fx1-$fx0}]
   foreach {bt bexx bexy} [draw_backwards_line $back] break
   foreach {bx0 by0 bx1 by1} [.c bbox $bt] break
   set bw [expr {$bx1-$bx0}]
   set dy [expr {-($by1 - $fy0 + $vsep)}]
-  .c move $bt 0 $dy
+  move_glyphs $bt 0 $dy
   set biny $dy
   set bexy [expr {$dy+$bexy}]
   set by0 [expr {$dy+$by0}]
   set by1 [expr {$dy+$by1}]
 
   if {$fw>$bw} {
     set dx [expr {($fw-$bw)/2}]
-    .c move $bt $dx 0
+    move_glyphs $bt $dx 0
     set bexx [expr {$dx+$bexx}]
     .c create line 0 $biny $dx $biny -width 2 -tags $bt
     .c create line $bexx $bexy $fx1 $bexy -width 2 -tags $bt -arrow first
     set mxx $fexx
   } elseif {$bw>$fw} {
     set dx [expr {($bw-$fw)/2}]
-    .c move $ft $dx 0
+    move_glyphs $ft $dx 0
     set fexx [expr {$dx+$fexx}]
     .c create line 0 0 $dx $fexy -width 2 -tags $ft
     .c create line $fexx $fexy $bx1 $fexy -width 2 -tags $ft
     set mxx $bexx
   }
-  .c addtag $tag withtag $bt
-  .c addtag $tag withtag $ft
-  .c dtag $bt $bt
-  .c dtag $ft $ft
-  .c move $tag $sep 0
+  retag $bt $tag
+  retag $ft $tag
+  move_glyphs $tag $sep 0
   set mxx [expr {$mxx+$sep}]
   .c create line 0 0 $sep 0 -width 2 -tags $tag
   draw_left_turnback $tag $sep 0 $biny down
   draw_right_turnback $tag $mxx $fexy $bexy
   foreach {x0 y0 x1 y1} [.c bbox $tag] break
@@ -485,11 +491,11 @@
     foreach {t texx texy} $m($i) break
     foreach {tx0 ty0 tx1 ty1} [.c bbox $t] break
     set w [expr {$tx1-$tx0}]
     set dx [expr {($mxw-$w)/2 + $x2}]
     if {$w>10 && $dx>$x2+10} {set dx [expr {$x2+10}]}
-    .c move $t $dx 0
+    move_glyphs $t $dx 0
     set texx [expr {$texx+$dx}]
     set m($i) [list $t $texx $texy]
     foreach {tx0 ty0 tx1 ty1} [.c bbox $t] break
     if {$i==0} {
       if {$dx>$x2} {set ax last} {set ax none}
@@ -500,11 +506,11 @@
          -width 2 -start 90 -extent -90 -tags $tag -style arc
       set btm $ty1
     } else {
       set dy [expr {$btm - $ty0 + $vsep}]
       if {$dy<2*$sep} {set dy [expr {2*$sep}]}
-      .c move $t 0 $dy
+      move_glyphs $t 0 $dy
       set texy [expr {$texy+$dy}]
       if {$dx>$x2} {
         .c create line $x2 $dy $dx $dy -width 2 -tags $tag -arrow last
         if {$dx<$xc-2} {set ax last} {set ax none}
         .c create line $texx $texy $x3 $texy -width 2 -tags $tag -arrow $ax
@@ -522,12 +528,11 @@
         .c create line $x4 [expr {$texy-$sep}] $x4 [expr {$exy+$sep}] \
                -width 2 -tags $tag
       }
       set btm [expr {$ty1+$dy}]
     }
-    .c addtag $tag withtag $t
-    .c dtag $t $t
+    retag $t $tag
   }
   return [list $tag $x5 $exy]   
 }
 
 proc draw_tail_branch {lx} {
@@ -549,21 +554,21 @@
 
   for {set i 0} {$i<$n} {incr i} {
     foreach {t texx texy} $m($i) break
     foreach {tx0 ty0 tx1 ty1} [.c bbox $t] break
     set dx [expr {$x2+10}]
-    .c move $t $dx 0
+    move_glyphs $t $dx 0
     foreach {tx0 ty0 tx1 ty1} [.c bbox $t] break
     if {$i==0} {
       .c create line 0 0 $dx 0 -width 2 -tags $tag -arrow last
       .c create arc -$sep 0 $sep [expr {$sep*2}] \
          -width 2 -start 90 -extent -90 -tags $tag -style arc
       set btm $ty1
     } else {
       set dy [expr {$btm - $ty0 + $vsep}]
       if {$dy<2*$sep} {set dy [expr {2*$sep}]}
-      .c move $t 0 $dy
+      move_glyphs $t 0 $dy
       if {$dx>$x2} {
         .c create line $x2 $dy $dx $dy -width 2 -tags $tag -arrow last
       }
       set y1 [expr {$dy-2*$sep}]
       .c create arc $x1 $y1 [expr {$x1+2*$sep}] $dy \
@@ -571,12 +576,11 @@
       if {$i==$n-1} {
         .c create line $x1 [expr {$dy-$sep}] $x1 $sep -width 2 -tags $tag
       }
       set btm [expr {$ty1+$dy}]
     }
-    .c addtag $tag withtag $t
-    .c dtag $t $t
+    retag $t $tag
   }
   return [list $tag 0 0]
 }
 
 proc draw_diagram {spec} {
@@ -637,11 +641,11 @@
   .c delete all
   wm deiconify .
   wm title . $name
   draw_diagram "line bullet [list $spec] bullet"
   foreach {x0 y0 x1 y1} [.c bbox all] break
-  .c move all [expr {2-$x0}] [expr {2-$y0}]
+  move_glyphs all [expr {2-$x0}] [expr {2-$y0}]
   foreach {x0 y0 x1 y1} [.c bbox all] break
   .c create rect -100 -100 [expr {$x1+100}] [expr {$y1+100}] \
      -fill white -outline white -tags bgrect
   .c lower bgrect
   .c config -width $x1 -height $y1