Use consistant $idx < 0 in stead of $idx != -1 for checking index meaning 'not found'

4 files changed, 8 insertions, 8 deletions

diff --git a/library/demos/entry3.tcl b/library/demos/entry3.tcl
index d4435c6..acde1b3 100644
--- a/library/demos/entry3.tcl
+++ b/library/demos/entry3.tcl
@@ -102,7 +102,7 @@ foreach {chars digit} {abc 2 def 3 ghi 4 jkl 5 mno 6 pqrs 7 tuv 8 wxyz 9} {
 
 proc validatePhoneChange {W vmode idx char} {
     global phoneNumberMap entry3content
-    if {$idx == -1} {return 1}
+    if {$idx < 0} {return 1}
     after idle [list $W configure -validate $vmode -invcmd bell]
     if {
 	!($idx<3 || $idx==6 || $idx==7 || $idx==11 || $idx>15) &&
diff --git a/library/demos/items.tcl b/library/demos/items.tcl
index be9214a..c3e14c1 100644
--- a/library/demos/items.tcl
+++ b/library/demos/items.tcl
@@ -250,14 +250,14 @@ proc itemsUnderArea {c} {
     set area [$c find withtag area]
     set items ""
     foreach i [$c find enclosed $areaX1 $areaY1 $areaX2 $areaY2] {
-	if {[lsearch [$c gettags $i] item] != -1} {
+	if {[lsearch [$c gettags $i] item] >= 0} {
 	    lappend items $i
 	}
     }
     puts stdout "Items enclosed by area: $items"
     set items ""
     foreach i [$c find overlapping $areaX1 $areaY1 $areaX2 $areaY2] {
-	if {[lsearch [$c gettags $i] item] != -1} {
+	if {[lsearch [$c gettags $i] item] >= 0} {
 	    lappend items $i
 	}
     }
diff --git a/library/demos/ixset b/library/demos/ixset
index 13235de..7cc35aa 100644
--- a/library/demos/ixset
+++ b/library/demos/ixset
@@ -54,7 +54,7 @@ proc readsettings {} {
     global screencyc ;	set screencyc	600
 
     set xfd [open "|xset q" r]
-    while {[gets $xfd line] > -1} {
+    while {[gets $xfd line] >= 0} {
 	switch -- [lindex $line 0] {
 	    auto {
 		set rpt [lindex $line 1]
diff --git a/library/demos/knightstour.tcl b/library/demos/knightstour.tcl
index b5cffa8..20e3d04 100644
--- a/library/demos/knightstour.tcl
+++ b/library/demos/knightstour.tcl
@@ -29,7 +29,7 @@ proc ValidMoves {square} {
     foreach pair {{-1 -2} {-2 -1} {-2 1} {-1 2} {1 2} {2 1} {2 -1} {1 -2}} {
         set col [expr {($square % 8) + [lindex $pair 0]}]
         set row [expr {($square / 8) + [lindex $pair 1]}]
-        if {$row > -1 && $row < 8 && $col > -1 && $col < 8} {
+        if {$row >= 0 && $row < 8 && $col >= 0 && $col < 8} {
             lappend moves [expr {$row * 8 + $col}]
         }
     }
@@ -41,7 +41,7 @@ proc CheckSquare {square} {
     variable visited
     set moves 0
     foreach test [ValidMoves $square] {
-        if {[lsearch -exact -integer $visited $test] == -1} {
+        if {[lsearch -exact -integer $visited $test] < 0} {
             incr moves
         }
     }
@@ -55,7 +55,7 @@ proc Next {square} {
     set minimum 9
     set nextSquare -1
     foreach testSquare [ValidMoves $square] {
-        if {[lsearch -exact -integer $visited $testSquare] == -1} {
+        if {[lsearch -exact -integer $visited $testSquare] < 0} {
             set count [CheckSquare $testSquare]
             if {$count < $minimum} {
                 set minimum $count
@@ -190,7 +190,7 @@ proc CreateGUI {} {
     ttk::button $dlg.tf.b1 -text Start -command [list Tour $dlg]
     ttk::button $dlg.tf.b2 -text Exit -command [list Exit $dlg]
     set square 0
-    for {set row 7} {$row != -1} {incr row -1} {
+    for {set row 7} {$row >= 0} {incr row -1} {
         for {set col 0} {$col < 8} {incr col} {
             if {(($col & 1) ^ ($row & 1))} {
                 set fill tan3 ; set dfill tan4