Eskil

        $::widgets($top,wLine1) insert end "\n" hl$::HighLightCount
        $::widgets($top,wLine2) insert end "\n" hl$::HighLightCount
        return [expr {($n1 > $n2 ? $n1 : $n2) + 1}]
    } else {
        return [expr {-($n1 > $n2 ? $n1 : $n2)}]
    }
}

# Insert two blocks of lines in the compare windows.
# No extra parsing at all.
proc insertMatchingBlocksNoParse {top block1 block2 line1 line2 details} {
    global doingLine1 doingLine2

    set n1 [llength $block1]
    set n2 [llength $block2]
    # Is this a change block, a delete block or an insert block?
    if {$n1 == 0} {set tag2 new2} else {set tag2 change}
    if {$n2 == 0} {set tag1 new1} else {set tag1 change}

    foreach line $block1 {
        insertLine $top 1 $doingLine1 $line $tag1
        incr doingLine1
    }
    foreach line $block2 {
        insertLine $top 2 $doingLine2 $line $tag2
        incr doingLine2
    }
    if {$n1 <= $n2} {
        for {set t $n1} {$t < $n2} {incr t} {
            emptyLine $top 1
        }
        addChange $top $n2 $tag2 $line1 $n1 $line2 $n2
        nextHighlight $top
    } elseif {$n2 < $n1} {
        for {set t $n2} {$t < $n1} {incr t} {
            emptyLine $top 2
        }
        addChange $top $n1 $tag1 $line1 $n1 $line2 $n2
        nextHighlight $top
    }
}

# Insert two blocks of lines in the compare windows.
proc insertMatchingBlocks {top block1 block2 line1 line2 details} {
    global doingLine1 doingLine2

    # A large block may take time.  Give a small warning.
    set n1 [llength $block1]

            incr doingLine1
            incr t
            if {$limit >= 0 && $t >= $limit} break
        }
        return
    }

    # Is this a change block, a delete block or an insert block?
    if {$n1 == 0} {set tag2 new2} else {set tag2 change}
    if {$n2 == 0} {set tag1 new1} else {set tag1 change}

    # Display all equal lines before next diff
    # If only diff is on, only skip a section if the blank
    # line replaces at least 3 lines.
    set limit -1

        if {$::eskil(filter) != "" &&  $::eskil(filterflag)} {
            addMapLines $top $n1
        } else {
            addChange $top $n1 change $line1 $n1 $line2 $n2
            nextHighlight $top
        }
    } else {
        # Collect blocks
        set block1 {}
        for {set t 0} {$t < $n1} {incr t} {
            gets $ch1 apa
            lappend block1 $apa
        }
        set block2 {}
        for {set t 0} {$t < $n2} {incr t} {
            gets $ch2 apa
            lappend block2 $apa
        }
        if {$n1 != 0 && $n2 != 0 && $Pref(parse) >= 2 && \
                ($n1 * $n2 < 1000 || $Pref(parse) == 3)} {
            # Full block parsing










            insertMatchingBlocks $top $block1 $block2 $line1 $line2 1
        } else {
            # No extra parsing at all.














            insertMatchingBlocksNoParse $top $block1 $block2 $line1 $line2 1








        }
    }
    # Empty return value
    return
}

proc enableRedo {top} {

            }
            continue
        }
        # No change block anymore. If one just ended, display it.
        if {[llength $lblock] > 0 || [llength $rblock] > 0} {
            set ::doingLine1 $lblockl
            set ::doingLine2 $rblockl
            # TODO: large/small block support
            #set Pref(parse) 2
            #if {$n1 != 0 && $n2 != 0 && $Pref(parse) >= 2 && \
                    #    ($n1 * $n2 < 1000 || $Pref(parse) == 3)} {
            # }
            insertMatchingBlocks $top $lblock $rblock $lblockl $rblockl 0
            set lblock {}
            set rblock {}
        }
        if {$lmode == "" && $rmode == ""} {
            insertLine $top 1 $lline $lstr
            insertLine $top 2 $rline $rstr

            continue
        }
    }
    # If the patch ended with a change block, display it.
    if {[llength $lblock] > 0 || [llength $rblock] > 0} {
        set ::doingLine1 $lblockl
        set ::doingLine2 $rblockl
        # TODO: large/small block support
        insertMatchingBlocks $top $lblock $rblock $lblockl $rblockl 0
        set lblock {}
        set rblock {}
    }
}

# Read a patch file and display it