Provided by: libdata-streamdeserializer-perl_0.06-1.1build4_amd64 bug

NAME

       Data::StreamDeserializer - non-blocking deserializer.

SYNOPSIS

           my $sr = new Data::StreamDeserializer
                   data => $very_big_dump;

           ... somewhere

           unless($sr->next) {
               # deserialization hasn't been done yet
           }

           ...

           if ($sr->next) {
               # deserialization has been done

               ...
               if ($sr->is_error) {
                   printf "%s\n",  $sr->error;
                   printf "Unparsed string tail: %s\n", $sr->tail;
               }

               my $result = $sr->result;           # first deserialized object
               my $result = $sr->result(first);    # the same

               my $results = $sr->result('all');   # all deserialized objects
                                                   # (ARRAYREF)
           }

           # stream deserializer
           $sr = new Data::StreamDeserializer;

           while(defined (my $block = read_next_data_block)) {
               $sr->next($block);
               ...
           }
           $sr->next(undef); # eof signal
           until ($sr->next) {
               ... do something
           }
           # all data were parsed

DESCRIPTION

       Sometimes You need to deserialize a lot of data. If You use 'eval' (or Safe->reval, etc)
       it can take You too much time. If Your code is executed in event machine it can be
       inadmissible. So using the module You can deserialize Your stream progressively and do
       something else between deserialization itearions.

   Recognized statements
       HASHES

        { something }

       ARRAYS

        [ something ]

       REFS

        \ something
        \[ ARRAY ]
        \{ HASH }

       Regexps

        qr{something}

       SCALARS

        "something"
        'something'
        q{something}
        qq{something}

METHODS

   new
       Creates new deserializer. It can receive a few named arguments:

       block_size

       The size of block which will be serialized in each 'next' cycle.  Default value is 512
       bytes.

       data

       If You know (have) all data to deserialize before constructing the object, You can use
       this argument.

       NOTE: You must not use the function part or next with arguments if You used this argument.

   block_size
       Set/get the same field.

   part
       Append a part of input data to serialize. If there is no argument (or undef), deserializer
       will know that there will be no data in the future.

   next
       Processes to parse next block_size bytes. Returns TRUE if an error was detected or all
       input datas were parsed.

   next_object
       The same as next but returns true after new object is found.  Drop previous results.

       For example You have the string:

           $str = "1, 2, [ 0, 1 ], { 'a' => 'b' }";

       You can extract objects:

           my $dsr = new Data::StreamDeserializer data => $str;

           1 until $dsr->next_object;
           my $first = $dsr->result;       # scalar: 1

           1 until $dsr->next_object;
           my $second = $dsr->result;      # scalar: 2

           1 until $dsr->next_object;
           my $third = $dsr->result;       # arrayref: [ 0, 1 ]

           1 until $dsr->next_object;
           my $third = $dsr->result;       # hashref: { 'a' => 'b' }

   skip_divider
       If You have a string:

           Object Object Object

       (there are no dividers between objects), You can call skip_divider after fetching the next
       object.

       Example:

           $str = "1 2 [ 0, 1 ]{ 'a' => 'b' }";

           my $dsr = new Data::StreamDeserializer data => $str;

           1 until $dsr->next_object;
           my $first = $dsr->result;       # scalar: 1

           $dsr->skip_divider;

           1 until $dsr->next_object;
           my $second = $dsr->result;      # scalar: 2

           $dsr->skip_divider;
           1 until $dsr->next_object;
           my $third = $dsr->result;       # arrayref: [ 0, 1 ]

       Important: You can't skip dividers inside nested object. The function will croak if You
       call it in the point that isn't between objects.

   is_error
       Returns TRUE if an error was detected.

   error
       Returns error string.

   tail
       Returns unparsed data.

   result
       Returns result of parsing. By default the function returns only the first parsed object.

       You can call the function with argument 'all' to get all parsed objects. In this case the
       function will receive ARRAYREF.

   is_done
       Returns TRUE if all input data were processed or an error was found.  If You didn't call
       part without arguments, and didn't call next or next_object with undef the function could
       return TRUE only if an error occured.

PRIVATE METHODS

   _push_error
       Pushes error into deserializer's error stack.

SEE ALSO

       DATA::StreamSerializer

BENCHMARKS

       This module is almost fully written using XS/C language. So it works a bit faster or
       slowly than CORE::eval.

       You can try a few scripts in benchmark/ directory. There are a few test arrays in this
       directory.

       Here are a few test results of my system.

   Array which contains 100 hashes:
       It works faster than eval:

           $ perl benchmark/ds_vs_eval.pl -n 1000 -b 512 benchmark/tests/01_100x10
           38296 bytes were read
           First deserializing by eval... done
           First deserializing by Data::DeSerializer... done
           Check if deserialized objects are same... done

           Starting 1000 iterations for eval... done (3.755 seconds)
           Starting 1000 iterations for Data::StreamDeserializer... done (3.059 seconds)

           Eval statistic:
                   1000 iterations were done
                   maximum deserialization time: 0.0041 seconds
                   minimum deserialization time: 0.0035 seconds
                   average deserialization time: 0.0036 seconds

           StreamDeserializer statistic:
                   1000 iterations were done
                   75000 SUBiterations were done
                   512 bytes in one block in one iteration
                   maximum deserialization time: 0.0045 seconds
                   minimum deserialization time: 0.0028 seconds
                   average deserialization time: 0.0029 seconds
                   average subiteration time:    0.00004 seconds

   Array which contains 1000 hashes:
       It works slowly than eval:

           $ perl benchmark/ds_vs_eval.pl -n 1000 -b 512 benchmark/tests/02_1000x10
           355623 bytes were read
           First deserializing by eval... done
           First deserializing by Data::DeSerializer... done
           Check if deserialized objects are same... done

           Starting 1000 iterations for eval... done (43.920 seconds)
           Starting 1000 iterations for Data::StreamDeserializer... done (71.668 seconds)

           Eval statistic:
                   1000 iterations were done
                   maximum deserialization time: 0.0490 seconds
                   minimum deserialization time: 0.0416 seconds
                   average deserialization time: 0.0426 seconds

           StreamDeserializer statistic:
                   1000 iterations were done
                   689000 SUBiterations were done
                   512 bytes in one block in one iteration
                   maximum deserialization time: 0.0773 seconds
                   minimum deserialization time: 0.0656 seconds
                   average deserialization time: 0.0690 seconds
                   average subiteration time:    0.00010 seconds

       You can see, that one block is parsed in a very short time period. So You can increase
       block_size value to reduce total parsing time.

       If block_size is equal string size the module works two times faster than eval:

           $ perl benchmark/ds_vs_eval.pl -n 1000 -b 355623 benchmark/tests/02_1000x10
           355623 bytes were read
           First deserializing by eval... done
           First deserializing by Data::DeSerializer... done
           Check if deserialized objects are same... done

           Starting 1000 iterations for eval... done (44.456 seconds)
           Starting 1000 iterations for Data::StreamDeserializer... done (19.702 seconds)

           Eval statistic:
                   1000 iterations were done
                   maximum deserialization time: 0.0474 seconds
                   minimum deserialization time: 0.0423 seconds
                   average deserialization time: 0.0431 seconds

           StreamDeserializer statistic:
                   1000 iterations were done
                   1000 SUBiterations were done
                   355623 bytes in one block in one iteration
                   maximum deserialization time: 0.0179 seconds
                   minimum deserialization time: 0.0168 seconds
                   average deserialization time: 0.0171 seconds
                   average subiteration time:    0.01705 seconds

AUTHOR

       Dmitry E. Oboukhov, <unera@debian.org>

COPYRIGHT AND LICENSE

       Copyright (C) 2011 by Dmitry E. Oboukhov

       This library is free software; you can redistribute it and/or modify it under the same
       terms as Perl itself, either Perl version 5.10.1 or, at your option, any later version of
       Perl 5 you may have available.

VCS

       The project is placed in my git repo. See here:
       <http://git.uvw.ru/?p=data-stream-deserializer;a=summary>