NAME
    Zug::XLSX::Huge - build large xlsx files without running out of RAM

VERSION
    Version 0.02

SYNOPSIS
        #!/usr/bin/env perl

        use strict;
        use warnings;

        use Zug::XLSX::Huge;

        my $columns = [
            { type => 'inlineStr', column_name => 'Some String' },
            { type => 'inlineStr', column_name => 'Some Other String' },
            { type => 'number',    column_name => 'A Number' },
            { type => 'number',    column_name => 'Another Number' },
        ];

        my ( $worksheet_builder, $finish_workbook ) = Zug::XLSX::Huge::make_callbacks( {
            filename       => '/tmp/' . time() . '.xlsx',
        } );

        my $worksheet_number = 1; # first worksheet
        my ( $add_row_to_first_worksheet, $finish_worksheet ) = $worksheet_builder->($worksheet_number, {
            worksheet_name => 'first worksheet',
            columns        => $columns,
        });


        my $other_columns = [
            { type => 'inlineStr', column_name => 'Some String' },
            { type => 'inlineStr', column_name => 'Some Other String' },
            { type => 'number',    column_name => 'A Number' },
            { type => 'number',    column_name => 'Another Number' },
            { type => 'number',    column_name => 'Yet Another Number' },
            { type => 'number',    column_name => 'And Yet Another Number' },
        ];

        #second worksheet
        my ( $add_row_to_second_worksheet, $finish_second_worksheet ) = $worksheet_builder->(2, {
            worksheet_name => 'second worksheet',
            columns        => $other_columns,
        });

        my $max   = 100;
        my $count = 0;
        while ( $count < $max ) {
            $add_row_to_first_worksheet->( 'a', 'b', $count, $count + 1 );
            $add_row_to_second_worksheet->('y', 'z', 30 % ($count + 1) , $count % 30, $count/15, $count*2);
            $count++;
        }

        $finish_worksheet->();
        $finish_second_worksheet->();

        $finish_workbook->();

STATUS
    Zug::XLSX::Huge is in early alpha stage, there are no unit tests or
    automatic tests, just a test script which must be run manually; no
    optimization attempted so far. Some xml elements in the files generated
    might not be really needed and will be removed.

DESCRIPTION
    I don't intend to extend it to be a competitor for Excel::Writer::XLSX
    and Zug::XLSX::Huge will always build very basic XLSX files. If you need
    to build XLSX files please use Excel::Writer::XLSX. Excel::Writer::XLSX
    also has the "set_optimization()" method to turn on RAM usage
    optimization with a few drawbacks which also apply to this module.

    I wrote Zug::XLSX::Huge to answer to a very special need: building huge
    excel files while using a predictable amount of RAM. To achieve this the
    files will not contain shared strings (unless you already know which
    strings should be shared -- feature still pending) and the files
    generated will most likely be larger than they could be when built with
    Excel::Writer::XLSX.

LIMITATIONS
    As of now Zug::XLSX::Huge supports only numeric values and inline
    strings. No formatting is possible.

  TODO
    split data automatically over multiple worksheets when a row count is
    reached
    shared strings
    row bufferring
    controlled RAM usage
    basic cell formatting (very low priority feature)
    formulas (very low priority feature)

AUTHOR
    Emil Nicolaie Perhinschi, "<emilper at gmail.com>"

BUGS
    Please report any bugs or feature requests at
    https://github.com/emil-perhinschi/zug-xlsx-huge.

LICENSE AND COPYRIGHT
    Copyright 2015 Emil Perhinschi.

    This program is free software; you can redistribute it and/or modify it
    under the terms of the the Artistic License (2.0). You may obtain a copy
    of the full license at:

    <http://www.perlfoundation.org/artistic_license_2_0>

    Any use, modification, and distribution of the Standard or Modified
    Versions is governed by this Artistic License. By using, modifying or
    distributing the Package, you accept this license. Do not use, modify,
    or distribute the Package, if you do not accept this license.

    If your Modified Version has been derived from a Modified Version made
    by someone other than you, you are nevertheless required to ensure that
    your Modified Version complies with the requirements of this license.

    This license does not grant you the right to use any trademark, service
    mark, tradename, or logo of the Copyright Holder.

    This license includes the non-exclusive, worldwide, free-of-charge
    patent license to make, have made, use, offer to sell, sell, import and
    otherwise transfer the Package with respect to any patent claims
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