For the callback, I did &$callback(. Here's a pretty-print: 
#!/usr/bin/perl

use strict;
use warnings;

sub cell_walk {
    my $self = shift @_;
    my ( $sheet_name, $x, $y, $callback ) = @_;
    my $Sheet = $$self{'book_handle'}->Worksheets($sheet_name);
    foreach $row( $row = $$x[0] ; $row <= $$y[0] ; ++$row ) {
        for ( my $col = $$x[1] ; $col <= $$y[1] ; ++$col ) {
            &$callback( $Sheet->Cells( $row, $col ) );
        }
    }
}

sub callback {
    return if not defined $_[0]{'Value'};
    if ( $_[0]{'Value'} =~ /^~~~/ ) {
        my (@a) = split( /__/, substr( $_[0]{'Value'}, 3 ), 0 );
        if ( scalar @a == 3 ) {
            $_[0]{'Value'} = $hl->get_single_LP( 'ADAS_VAL_RAW', @a );
        }
        if ( scalar @a == 4 ) {
            $_[0]{'Value'} = $hl->accu_LP( 'ADAS_VAL_NORM', @a );
        }
    }
}

[download]
Does that help?

In reply to Re: how organize code by Khen1950fx
in thread how organize code in callback mode by xiaoyafeng

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