Eskil

        lappend marks mergee$t [$w index insert]
        set diff($top,mergeSelection,$t) 2
        incr t
    }
    foreach {mark index} $marks {
        $w mark set $mark $index
    }
    # Add fences to simplify some handling later
    $w mark set mergee-2 1.0
    $w mark set mergee-1 1.0
    $w mark set merges$t end
    $w mark set merges[expr {$t + 1}] end

    set diff($top,curMerge) 0
    set diff($top,curMergeSel) 2
    $w tag configure merge0 -foreground red
    showDiff $top 0
    update
    # If there is any diff, show the first
    if {$t > 0} {

    set diff($top,mergeSelection,$no) $new

    set i [expr {$no * 2 + 1}]
    set diffLeft [lindex $diff($top,leftMergeData) $i]
    set diffRight [lindex $diff($top,rightMergeData) $i]

    # Temporarily switch surrounding marks
    # Two steps are enough since there can't be consecutive empty areas
    # The one before and/or the one after the one being switch might
    # be empty.
    $w mark gravity mergee[expr {$no - 2}] left
    $w mark gravity mergee[expr {$no - 1}] left
    $w mark gravity merges[expr {$no + 1}] right
    $w mark gravity merges[expr {$no + 2}] right

    if {$diff($top,mergeSelection,$no) == 12} {
        $w insert merges$no $diffLeft$diffRight merge$no
    } elseif {$diff($top,mergeSelection,$no) == 21} {
        $w insert merges$no $diffRight$diffLeft merge$no
    } elseif {$diff($top,mergeSelection,$no) == 1} {
        $w insert merges$no $diffLeft merge$no
    } elseif {$diff($top,mergeSelection,$no) == 2} {
        $w insert merges$no $diffRight merge$no
    }
    # Switch back surrounding marks
    $w mark gravity mergee[expr {$no - 2}] right
    $w mark gravity mergee[expr {$no - 1}] right
    $w mark gravity merges[expr {$no + 1}] left
    $w mark gravity merges[expr {$no + 2}] left
}

# Save the merge result.
proc saveMerge {top} {
    set w $top.merge.t

    if {$::diff($top,mergeFile) eq "" && $::diff($top,mode) eq "conflict"} {