NAME

Latin2 - Source code filter to escape Latin-2 script

Install and Usage

There are two steps there:

You'll have to download Latin2.pm and Elatin2.pm and put it in your perl lib directory.
You'll need to write "use Latin2;" at head of the script.

SYNOPSIS

use Latin2;
use Latin2 ver.sion;             --- require minimum version
use Latin2 ver.sion.0;           --- expects version (match or die)

# "no Latin2;" not supported

or

$ perl Latin2.pm Latin-2_script.pl > Escaped_script.pl.e

then

$ perl Escaped_script.pl.e

Latin-2_script.pl  --- script written in Latin-2
Escaped_script.pl.e --- escaped script

subroutines:
  Latin2::eval(...);
dummy functions:
  utf8::upgrade(...);
  utf8::downgrade(...);
  utf8::encode(...);
  utf8::decode(...);
  utf8::is_utf8(...);
  utf8::valid(...);
  bytes::chr(...);
  bytes::index(...);
  bytes::length(...);
  bytes::ord(...);
  bytes::rindex(...);
  bytes::substr(...);

ABSTRACT

Latin2 software is "middleware" between perl interpreter and your Perl script written in Latin-2.

Perl is optimized for problems which are about 90% working with text and about 10% everything else. Even if this "text" doesn't contain Latin-2, Perl3 or later can treat Latin-2 as binary data.

By "use Latin2;", it automatically interpret your script as Latin-2. The various functions of perl including a regular expression can treat Latin-2 now. The function length treats length per byte. This software does not use UTF8 flag.

Yet Another Future Of

JPerl is very useful software. -- Oops, note, this "JPerl" means "Japanized Perl" or "Japanese Perl". Therefore, it is unrelated to JPerl of the following.

JPerl is an implementation of Perl written in Java.
http://www.javainc.com/projects/jperl/

jPerl - Perl on the JVM
http://www.dzone.com/links/175948.html

Jamie's PERL scripts for bioinformatics
http://code.google.com/p/jperl/

jperl (Jonathan Perl)
https://github.com/jperl

Now, the last version of JPerl is 5.005_04 and is not maintained now.

Japanization modifier WATANABE Hirofumi said,

"Because WATANABE am tired I give over maintaing JPerl."

at Slide #15: "The future of JPerl" of

ftp://ftp.oreilly.co.jp/pcjp98/watanabe/jperlconf.ppt

in The Perl Confernce Japan 1998.

When I heard it, I thought that someone excluding me would maintain JPerl. And I slept every night hanging a sock. Night and day, I kept having hope. After 10 years, I noticed that white beard exists in the sock :-)

This software is a source code filter to escape Perl script encoded by Latin-2 given from STDIN or command line parameter. The character code is never converted by escaping the script. Neither the value of the character nor the length of the character string change even if it escapes.

I learned the following things from the successful software.

Upper Compatibility like Perl4 to Perl5
Maximum Portability like jcode.pl
Remains One Language Handling Raw Latin-2, Doesn't Use UTF8 flag like JPerl
Remains One Interpreter like Encode module
Code Set Independent like Ruby
Monolithic Script like cpanminus
There's more than one way to do it like Perl itself

I am excited about this software and Perl's future --- I hope you are too.

JRE: JPerl Runtime Environment

+---------------------------------------+
|        JPerl Application Script       | Your Script
+---------------------------------------+
|  Source Code Filter, Runtime Routine  | ex. Latin2.pm, Elatin2.pm
+---------------------------------------+
|          PVM 5.00503 or later         | ex. perl 5.00503
+---------------------------------------+

A Perl Virtual Machine (PVM) enables a set of computer software programs and data structures to use a virtual machine model for the execution of other computer programs and scripts. The model used by a PVM accepts a form of computer intermediate language commonly referred to as Perl byteorientedcode. This language conceptually represents the instruction set of a byte-oriented, capability architecture.

Basic Idea of Source Code Filter

I discovered this mail again recently.

[Tokyo.pm] jus Benkyoukai

http://mail.pm.org/pipermail/tokyo-pm/1999-September/001854.html

save as: SJIS.pm

package SJIS;
use Filter::Util::Call;
sub multibyte_filter {
    my $status;
    if (($status = filter_read()) > 0 ) {
        s/([\x81-\x9f\xe0-\xef])([\x40-\x7e\x80-\xfc])/
            sprintf("\\x%02x\\x%02x",ord($1),ord($2))
        /eg;
    }
    $status;
}
sub import {
    filter_add(\&multibyte_filter);
}
1;

I am glad that I could confirm my idea is not so wrong.

Command-line Wildcard Expansion on DOS-like Systems

The default command shells on DOS-like systems (COMMAND.COM or cmd.exe or Win95Cmd.exe) do not expand wildcard arguments supplied to programs. Instead, import of Elatin2.pm works well.

in Elatin2.pm
#
# @ARGV wildcard globbing
#
sub import {

    if ($^O =~ /\A (?: MSWin32 | NetWare | symbian | dos ) \z/oxms) {
        my @argv = ();
        for (@ARGV) {

            # has space
            if (/\A (?:$q_char)*? [ ] /oxms) {
                if (my @glob = Elatin2::glob(qq{"$_"})) {
                    push @argv, @glob;
                }
                else {
                    push @argv, $_;
                }
            }

            # has wildcard metachar
            elsif (/\A (?:$q_char)*? [*?] /oxms) {
                if (my @glob = Elatin2::glob($_)) {
                    push @argv, @glob;
                }
                else {
                    push @argv, $_;
                }
            }

            # no wildcard globbing
            else {
                push @argv, $_;
            }
        }
        @ARGV = @argv;
    }
}

Software Composition

Latin2.pm               --- source code filter to escape Latin-2
Elatin2.pm              --- run-time routines for Latin2.pm

Upper Compatibility by Escaping

This software adds the function by 'Escaping' it always, and nothing of the past is broken. Therefore, 'Possible job' never becomes 'Impossible job'. This approach is effective in the field where the retreat is never permitted. It means incompatible upgrade of Perl should be rewound.

Escaping Your Script (You do)

You need write 'use Latin2;' in your script.

---------------------
You do
---------------------
use Latin2;
---------------------

Calling 'Elatin2::ignorecase()' (Latin2 software provides)

Latin2 software applies calling 'Elatin2::ignorecase()' instead of /i modifier.

--------------------------------------------------------------------------------
Before                  After
--------------------------------------------------------------------------------
m/...$var.../i          m/...@{[Elatin2::ignorecase($var)]}.../
--------------------------------------------------------------------------------

Escaping Character Classes (Elatin2.pm provides)

The character classes are redefined as follows to backward compatibility.

---------------------------------------------------------------
Before        After
---------------------------------------------------------------
 .            ${Elatin2::dot}
              ${Elatin2::dot_s}    (/s modifier)
\d            [0-9]              (universally)
\s            \s
\w            [0-9A-Z_a-z]       (universally)
\D            ${Elatin2::eD}
\S            ${Elatin2::eS}
\W            ${Elatin2::eW}
\h            [\x09\x20]
\v            [\x0A\x0B\x0C\x0D]
\H            ${Elatin2::eH}
\V            ${Elatin2::eV}
\C            [\x00-\xFF]
\X            X                  (so, just 'X')
\R            ${Elatin2::eR}
\N            ${Elatin2::eN}
---------------------------------------------------------------

Also POSIX-style character classes.

---------------------------------------------------------------
Before        After
---------------------------------------------------------------
[:alnum:]     [\x30-\x39\x41-\x5A\x61-\x7A]
[:alpha:]     [\x41-\x5A\x61-\x7A]
[:ascii:]     [\x00-\x7F]
[:blank:]     [\x09\x20]
[:cntrl:]     [\x00-\x1F\x7F]
[:digit:]     [\x30-\x39]
[:graph:]     [\x21-\x7F]
[:lower:]     [\x61-\x7A]
              [\x41-\x5A\x61-\x7A]     (/i modifier)
[:print:]     [\x20-\x7F]
[:punct:]     [\x21-\x2F\x3A-\x3F\x40\x5B-\x5F\x60\x7B-\x7E]
[:space:]     [\s\x0B]
[:upper:]     [\x41-\x5A]
              [\x41-\x5A\x61-\x7A]     (/i modifier)
[:word:]      [\x30-\x39\x41-\x5A\x5F\x61-\x7A]
[:xdigit:]    [\x30-\x39\x41-\x46\x61-\x66]
[:^alnum:]    ${Elatin2::not_alnum}
[:^alpha:]    ${Elatin2::not_alpha}
[:^ascii:]    ${Elatin2::not_ascii}
[:^blank:]    ${Elatin2::not_blank}
[:^cntrl:]    ${Elatin2::not_cntrl}
[:^digit:]    ${Elatin2::not_digit}
[:^graph:]    ${Elatin2::not_graph}
[:^lower:]    ${Elatin2::not_lower}
              ${Elatin2::not_lower_i}    (/i modifier)
[:^print:]    ${Elatin2::not_print}
[:^punct:]    ${Elatin2::not_punct}
[:^space:]    ${Elatin2::not_space}
[:^upper:]    ${Elatin2::not_upper}
              ${Elatin2::not_upper_i}    (/i modifier)
[:^word:]     ${Elatin2::not_word}
[:^xdigit:]   ${Elatin2::not_xdigit}
---------------------------------------------------------------

\b and \B are redefined as follows to backward compatibility.

---------------------------------------------------------------
Before      After
---------------------------------------------------------------
\b          ${Elatin2::eb}
\B          ${Elatin2::eB}
---------------------------------------------------------------

Definitions in Elatin2.pm.

---------------------------------------------------------------------------------------------------------------------------------------------------------
After                    Definition
---------------------------------------------------------------------------------------------------------------------------------------------------------
${Elatin2::dot}            qr{(?>[^\x0A])};
${Elatin2::dot_s}          qr{(?>[\x00-\xFF])};
${Elatin2::eD}             qr{(?>[^0-9])};
${Elatin2::eS}             qr{(?>[^\s])};
${Elatin2::eW}             qr{(?>[^0-9A-Z_a-z])};
${Elatin2::eH}             qr{(?>[^\x09\x20])};
${Elatin2::eV}             qr{(?>[^\x0A\x0B\x0C\x0D])};
${Elatin2::eR}             qr{(?>\x0D\x0A|[\x0A\x0D])};
${Elatin2::eN}             qr{(?>[^\x0A])};
${Elatin2::not_alnum}      qr{(?>[^\x30-\x39\x41-\x5A\x61-\x7A])};
${Elatin2::not_alpha}      qr{(?>[^\x41-\x5A\x61-\x7A])};
${Elatin2::not_ascii}      qr{(?>[^\x00-\x7F])};
${Elatin2::not_blank}      qr{(?>[^\x09\x20])};
${Elatin2::not_cntrl}      qr{(?>[^\x00-\x1F\x7F])};
${Elatin2::not_digit}      qr{(?>[^\x30-\x39])};
${Elatin2::not_graph}      qr{(?>[^\x21-\x7F])};
${Elatin2::not_lower}      qr{(?>[^\x61-\x7A])};
${Elatin2::not_lower_i}    qr{(?>[^\x41-\x5A\x61-\x7A])}; # Perl 5.16 compatible
# ${Elatin2::not_lower_i}    qr{(?>[\x00-\xFF])};                   # older Perl compatible
${Elatin2::not_print}      qr{(?>[^\x20-\x7F])};
${Elatin2::not_punct}      qr{(?>[^\x21-\x2F\x3A-\x3F\x40\x5B-\x5F\x60\x7B-\x7E])};
${Elatin2::not_space}      qr{(?>[^\s\x0B])};
${Elatin2::not_upper}      qr{(?>[^\x41-\x5A])};
${Elatin2::not_upper_i}    qr{(?>[^\x41-\x5A\x61-\x7A])}; # Perl 5.16 compatible
# ${Elatin2::not_upper_i}    qr{(?>[\x00-\xFF])};                   # older Perl compatible
${Elatin2::not_word}       qr{(?>[^\x30-\x39\x41-\x5A\x5F\x61-\x7A])};
${Elatin2::not_xdigit}     qr{(?>[^\x30-\x39\x41-\x46\x61-\x66])};

# This solution is not perfect. I beg better solution from you who are reading this.
${Elatin2::eb}             qr{(?:\A(?=[0-9A-Z_a-z])|(?<=[\x00-\x2F\x40\x5B-\x5E\x60\x7B-\xFF])(?=[0-9A-Z_a-z])|(?<=[0-9A-Z_a-z])(?=[\x00-\x2F\x40\x5B-\x5E\x60\x7B-\xFF]|\z))};
${Elatin2::eB}             qr{(?:(?<=[0-9A-Z_a-z])(?=[0-9A-Z_a-z])|(?<=[\x00-\x2F\x40\x5B-\x5E\x60\x7B-\xFF])(?=[\x00-\x2F\x40\x5B-\x5E\x60\x7B-\xFF]))};
---------------------------------------------------------------------------------------------------------------------------------------------------------

Un-Escaping \ of \b{}, \B{}, \N{}, \p{}, \P{}, and \X (Latin2 software provides)

Latin2 software removes '\' at head of alphanumeric regexp metasymbols \b{}, \B{}, \N{}, \p{}, \P{} and \X. By this method, you can avoid the trap of the abstraction.

See also, Deprecate literal unescaped "{" in regexes. http://perl5.git.perl.org/perl.git/commit/2a53d3314d380af5ab5283758219417c6dfa36e9

------------------------------------
Before           After
------------------------------------
\b{...}          b\{...}
\B{...}          B\{...}
\N{CHARNAME}     N\{CHARNAME}
\p{L}            p\{L}
\p{^L}           p\{^L}
\p{\^L}          p\{\^L}
\pL              pL
\P{L}            P\{L}
\P{^L}           P\{^L}
\P{\^L}          P\{\^L}
\PL              PL
\X               X
------------------------------------

Escaping Built-in Functions (Latin2 software provides)

Insert 'Elatin2::' at head of function name. Elatin2.pm provides your script Elatin2::* subroutines.

-------------------------------------------
Before      After            Works as
-------------------------------------------
lc          Elatin2::lc        Character
lcfirst     Elatin2::lcfirst   Character
uc          Elatin2::uc        Character
ucfirst     Elatin2::ucfirst   Character
fc          Elatin2::fc        Character
chr         Elatin2::chr       Character
glob        Elatin2::glob      Character
-------------------------------------------

------------------------------------------------------------------------------------------------------------------------
Before                   After
------------------------------------------------------------------------------------------------------------------------
use Perl::Module;        BEGIN { require 'Perl/Module.pm'; Perl::Module->import() if Perl::Module->can('import'); }
use Perl::Module @list;  BEGIN { require 'Perl/Module.pm'; Perl::Module->import(@list) if Perl::Module->can('import'); }
use Perl::Module ();     BEGIN { require 'Perl/Module.pm'; }
no Perl::Module;         BEGIN { require 'Perl/Module.pm'; Perl::Module->unimport() if Perl::Module->can('unimport'); }
no Perl::Module @list;   BEGIN { require 'Perl/Module.pm'; Perl::Module->unimport(@list) if Perl::Module->can('unimport'); }
no Perl::Module ();      BEGIN { require 'Perl/Module.pm'; }
------------------------------------------------------------------------------------------------------------------------

Yada Yada Operator (Latin2 software provides)

The yada yada operator (noted ...) is a placeholder for code. Perl parses it
without error, but when you try to execute a yada yada, it throws an exception
with the text Unimplemented:

sub unimplemented { ... }
eval { unimplemented() };
if ( $@ eq 'Unimplemented' ) {
    print "I found the yada yada!\n";
}

You can only use the yada yada to stand in for a complete statement. These
examples of the yada yada work:

{ ... }
sub foo { ... }
...;
eval { ... };
sub foo {
    my( $self ) = shift;
    ...;
}
do { my $n; ...; print 'Hurrah!' };

The yada yada cannot stand in for an expression that is part of a larger statement
since the ... is also the three-dot version of the range operator
(see "Range Operators"). These examples of the yada yada are still syntax errors:

print ...;
open my($fh), '>', '/dev/passwd' or ...;
if ( $condition && ... ) { print "Hello\n" };

There are some cases where Perl can't immediately tell the difference between an
expression and a statement. For instance, the syntax for a block and an anonymous
hash reference constructor look the same unless there's something in the braces that
give Perl a hint. The yada yada is a syntax error if Perl doesn't guess that the
{ ... } is a block. In that case, it doesn't think the ... is the yada yada because
it's expecting an expression instead of a statement:

my @transformed = map { ... } @input;  # syntax error

You can use a ; inside your block to denote that the { ... } is a block and not a
hash reference constructor. Now the yada yada works:

my @transformed = map {; ... } @input; # ; disambiguates
my @transformed = map { ...; } @input; # ; disambiguates

Un-Escaping bytes::* Subroutines (Latin2 software provides)

Latin2 software removes 'bytes::' at head of subroutine name.

---------------------------------------
Before           After     Works as
---------------------------------------
bytes::chr       chr       Byte
bytes::index     index     Byte
bytes::length    length    Byte
bytes::ord       ord       Byte
bytes::rindex    rindex    Byte
bytes::substr    substr    Byte
---------------------------------------

Ignore Pragmas and Modules

-----------------------------------------------------------
Before                    After
-----------------------------------------------------------
use strict;               use strict; no strict qw(refs);
use 5.12.0;               use 5.12.0; no strict qw(refs);
require utf8;             # require utf8;
require bytes;            # require bytes;
require charnames;        # require charnames;
require I18N::Japanese;   # require I18N::Japanese;
require I18N::Collate;    # require I18N::Collate;
require I18N::JExt;       # require I18N::JExt;
require File::DosGlob;    # require File::DosGlob;
require Wild;             # require Wild;
require Wildcard;         # require Wildcard;
require Japanese;         # require Japanese;
use utf8;                 # use utf8;
use bytes;                # use bytes;
use charnames;            # use charnames;
use I18N::Japanese;       # use I18N::Japanese;
use I18N::Collate;        # use I18N::Collate;
use I18N::JExt;           # use I18N::JExt;
use File::DosGlob;        # use File::DosGlob;
use Wild;                 # use Wild;
use Wildcard;             # use Wildcard;
use Japanese;             # use Japanese;
no utf8;                  # no utf8;
no bytes;                 # no bytes;
no charnames;             # no charnames;
no I18N::Japanese;        # no I18N::Japanese;
no I18N::Collate;         # no I18N::Collate;
no I18N::JExt;            # no I18N::JExt;
no File::DosGlob;         # no File::DosGlob;
no Wild;                  # no Wild;
no Wildcard;              # no Wildcard;
no Japanese;              # no Japanese;
-----------------------------------------------------------

Comment out pragma to ignore utf8 environment, and Elatin2.pm provides these
functions.

Dummy utf8::upgrade

$num_octets = utf8::upgrade($string);

Returns the number of octets necessary to represent the string.

Dummy utf8::downgrade

$success = utf8::downgrade($string[, FAIL_OK]);

Returns true always.

Dummy utf8::encode

utf8::encode($string);

Returns nothing.

Dummy utf8::decode

$success = utf8::decode($string);

Returns true always.

Dummy utf8::is_utf8

$flag = utf8::is_utf8(STRING);

Returns false always.

Dummy utf8::valid

$flag = utf8::valid(STRING);

Returns true always.

Dummy bytes::chr
```
This subroutine is same as chr.
```
Dummy bytes::index
```
This subroutine is same as index.
```
Dummy bytes::length
```
This subroutine is same as length.
```
Dummy bytes::ord
```
This subroutine is same as ord.
```
Dummy bytes::rindex
```
This subroutine is same as rindex.
```
Dummy bytes::substr
```
This subroutine is same as substr.
```

Environment Variable

This software uses the flock function for exclusive control. The execution of the
program is blocked until it becomes possible to read or write the file.
You can have it not block in the flock function by defining environment variable
CHAR_NONBLOCK.

Example:

  SET CHAR_NONBLOCK=1

(The value '1' doesn't have the meaning)

BUGS, LIMITATIONS, and COMPATIBILITY

I have tested and verified this software using the best of my ability. However, a software containing much regular expression is bound to contain some bugs. Thus, if you happen to find a bug that's in Latin2 software and not your own program, you can try to reduce it to a minimal test case and then report it to the following author's address. If you have an idea that could make this a more useful tool, please let everyone share it.

(dummy item to avoid Test::Pod error)
cloister of regular expression

The cloister (?s) and (?i) of a regular expression will not be implemented for the time being. Cloister (?s) can be substituted with the .(dot) and \N on /s modifier. Cloister (?i) can be substituted with \F...\E.
Modifier /a /d /l and /u of Regular Expression

The concept of this software is not to use two or more encoding methods as literal string and literal of regexp in one Perl script. Therefore, modifier /a, /d, /l, and /u are not supported. \d means [0-9] universally.
Named Character

A named character, such \N{GREEK SMALL LETTER EPSILON}, \N{greek:epsilon}, or \N{epsilon} is not supported.
Unicode Properties (aka Character Properties) of Regular Expression

Unicode properties (aka character properties) of regexp are not available. Also (?[]) in regexp of Perl 5.18 is not available. There is no plans to currently support these.
Delimiter of String and Regexp

qq//, q//, qw//, qx//, qr//, m//, s///, tr///, and y/// can't use a wide character as the delimiter.

\b{...} Boundaries in Regular Expressions

Following \b{...} available starting in v5.22 are not supported.

\b{gcb} or \b{g}   Unicode "Grapheme Cluster Boundary"
\b{sb}             Unicode "Sentence Boundary"
\b{wb}             Unicode "Word Boundary"
\B{gcb} or \B{g}   Unicode "Grapheme Cluster Boundary" doesn't match
\B{sb}             Unicode "Sentence Boundary" doesn't match
\B{wb}             Unicode "Word Boundary" doesn't match

AUTHOR

INABA Hitoshi <ina@cpan.org>

This project was originated by INABA Hitoshi.

LICENSE AND COPYRIGHT

This software is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic.

This software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

My Goal

P.401 See chapter 15: Unicode of ISBN 0-596-00027-8 Programming Perl Third Edition.

Before the introduction of Unicode support in perl, The eq operator just compared the byte-strings represented by two scalars. Beginning with perl 5.8, eq compares two byte-strings with simultaneous consideration of the UTF8 flag.

/* You are not expected to understand this */

 Information processing model beginning with perl 5.8

   +----------------------+---------------------+
   |     Text strings     |                     |
   +----------+-----------|    Binary strings   |
   |  UTF-8   |  Latin-1  |                     |
   +----------+-----------+---------------------+
   | UTF8     |            Not UTF8             |
   | Flagged  |            Flagged              |
   +--------------------------------------------+
   http://perl-users.jp/articles/advent-calendar/2010/casual/4

 Confusion of Perl string model is made from double meanings of
 "Binary string."
 Meanings of "Binary string"
 1. Non-Text string
 2. Digital octet string

 Let's draw again using those term.

   +----------------------+---------------------+
   |     Text strings     |                     |
   +----------+-----------|   Non-Text strings  |
   |  UTF-8   |  Latin-1  |                     |
   +----------+-----------+---------------------+
   | UTF8     |            Not UTF8             |
   | Flagged  |            Flagged              |
   +--------------------------------------------+
   |            Digital octet string            |
   +--------------------------------------------+

There are people who don't agree to change in the character string processing model of Perl 5.8. It is impossible to get to agree it to majority of Perl user who hardly ever use Perl. How to solve it by returning to a original method, let's drag out page 402 of the old dusty Programming Perl, 3rd ed. again.

Information processing model beginning with perl3 or this software
of UNIX/C-ism.

  +--------------------------------------------+
  |    Text string as Digital octet string     |
  |    Digital octet string as Text string     |
  +--------------------------------------------+
  |       Not UTF8 Flagged, No Mojibake        |
  +--------------------------------------------+

In UNIX Everything is a File
- In UNIX everything is a stream of bytes
- In UNIX the filesystem is used as a universal name space

Native Encoding Scripting
- native encoding of file contents
- native encoding of file name on filesystem
- native encoding of command line
- native encoding of environment variable
- native encoding of API
- native encoding of network packet
- native encoding of database

Ideally, I'd like to achieve these five Goals:

Goal #1:

Old byte-oriented programs should not spontaneously break on the old byte-oriented data they used to work on.

This goal has been achieved by that this software is additional code for perl like utf8 pragma. Perl should work same as past Perl if added nothing.

Goal #2:

Old byte-oriented programs should magically start working on the new character-oriented data when appropriate.

Still now, 1 octet is counted with 1 by built-in functions length, substr, index, rindex, and pos that handle length and position of string. In this part, there is no change. The length of 1 character of 2 octet code is 2.

On the other hand, the regular expression in the script is added the multibyte anchoring processing with this software, instead of you.

figure of Goal #1 and Goal #2.

                         GOAL#1  GOAL#2
                  (a)     (b)     (c)     (d)     (e)
+--------------+-------+-------+-------+-------+-------+
| data         |  Old  |  Old  |  New  |  Old  |  New  |
+--------------+-------+-------+-------+-------+-------+
| script       |  Old  |      Old      |      New      |
+--------------+-------+---------------+---------------+
| interpreter  |  Old  |              New              |
+--------------+-------+-------------------------------+
Old --- Old byte-oriented
New --- New character-oriented

There is a combination from (a) to (e) in data, script, and interpreter of old and new. Let's add the Encode module and this software did not exist at time of be written this document and JPerl did exist.

                  (a)     (b)     (c)     (d)     (e)
                                JPerl,japerl    Encode,Latin2
+--------------+-------+-------+-------+-------+-------+
| data         |  Old  |  Old  |  New  |  Old  |  New  |
+--------------+-------+-------+-------+-------+-------+
| script       |  Old  |      Old      |      New      |
+--------------+-------+---------------+---------------+
| interpreter  |  Old  |              New              |
+--------------+-------+-------------------------------+
Old --- Old byte-oriented
New --- New character-oriented

The reason why JPerl is very excellent is that it is at the position of (c). That is, it is not necessary to do a special description to the script to process new character-oriented string. (May the japerl take over JPerl!)

Goal #3:

Programs should run just as fast in the new character-oriented mode as in the old byte-oriented mode.

It is impossible. Because the following time is necessary.

(1) Time of escape script for old byte-oriented perl.

Someday, I want to ask Larry Wall about this goal in the elevator.
Goal #4:

Perl should remain one language, rather than forking into a byte-oriented Perl and a character-oriented Perl.

JPerl remains one Perl language by forking to two interpreters. However, the Perl core team did not desire fork of the interpreter. As a result, Perl language forked contrary to goal #4.

A character-oriented perl is not necessary to make it specially, because a byte-oriented perl can already treat the binary data. This software is only an application program of byte-oriented Perl, a filter program.

And you will get support from the Perl community, when you solve the problem by the Perl script.

Latin2 software remains one language and one interpreter.
Goal #5:

JPerl users will be able to maintain JPerl by Perl.

May the JPerl be with you, always.

Back when Programming Perl, 3rd ed. was written, UTF8 flag was not born and Perl is designed to make the easy jobs easy. This software provides programming environment like at that time.

Perl's motto

  Some computer scientists (the reductionists, in particular) would
 like to deny it, but people have funny-shaped minds. Mental geography
 is not linear, and cannot be mapped onto a flat surface without
 severe distortion. But for the last score years or so, computer
 reductionists have been first bowing down at the Temple of Orthogonality,
 then rising up to preach their ideas of ascetic rectitude to any who
 would listen.

  Their fervent but misguided desire was simply to squash your mind to
 fit their mindset, to smush your patterns of thought into some sort of
 Hyperdimensional Flatland. It's a joyless existence, being smushed.
 --- Learning Perl on Win32 Systems

 If you think this is a big headache, you're right. No one likes
 this situation, but Perl does the best it can with the input and
 encodings it has to deal with. If only we could reset history and
 not make so many mistakes next time.
 --- Learning Perl 6th Edition

  The most important thing for most people to know about handling
 Unicode data in Perl, however, is that if you don't ever use any Uni-
 code data -- if none of your files are marked as UTF-8 and you don't
 use UTF-8 locales -- then you can happily pretend that you're back in
 Perl 5.005_03 land; the Unicode features will in no way interfere with
 your code unless you're explicitly using them. Sometimes the twin
 goals of embracing Unicode but not disturbing old-style byte-oriented
 scripts has led to compromise and confusion, but it's the Perl way to
 silently do the right thing, which is what Perl ends up doing.
 --- Advanced Perl Programming, 2nd Edition

ACKNOWLEDGEMENTS

This software was made referring to software and the document that the following hackers or persons had made. I am thankful to all persons.

Rick Yamashita, Shift_JIS
ttp://furukawablog.spaces.live.com/Blog/cns!1pmWgsL289nm7Shn7cS0jHzA!2225.entry (dead link)
ttp://shino.tumblr.com/post/116166805/1981-us-jis
(add 'h' at head)
http://www.wdic.org/w/WDIC/%E3%82%B7%E3%83%95%E3%83%88JIS

Larry Wall, Perl
http://www.perl.org/

Kazumasa Utashiro, jcode.pl
http://search.cpan.org/~utashiro/
ftp://ftp.iij.ad.jp/pub/IIJ/dist/utashiro/perl/
http://log.utashiro.com/pub/2006/07/jkondo_a580.html

Jeffrey E. F. Friedl, Mastering Regular Expressions
http://regex.info/

SADAHIRO Tomoyuki, The right way of using Shift_JIS
http://homepage1.nifty.com/nomenclator/perl/shiftjis.htm
http://search.cpan.org/~sadahiro/

Yukihiro "Matz" Matsumoto, YAPC::Asia2006 Ruby on Perl(s)
http://www.rubyist.net/~matz/slides/yapc2006/

jscripter, For jperl users
http://homepage1.nifty.com/kazuf/jperl.html

Bruce., Unicode in Perl
http://www.rakunet.org/tsnet/TSabc/18/546.html

Hiroaki Izumi, Perl5.8/Perl5.10 is not useful on the Windows.
http://dl.dropbox.com/u/23756062/perlwin.html
https://sites.google.com/site/hiroa63iz/perlwin

TSUKAMOTO Makio, Perl memo/file path of Windows
http://digit.que.ne.jp/work/wiki.cgi?Perl%E3%83%A1%E3%83%A2%2FWindows%E3%81%A7%E3%81%AE%E3%83%95%E3%82%A1%E3%82%A4%E3%83%AB%E3%83%91%E3%82%B9

chaichanPaPa, Matching Shift_JIS file name
http://d.hatena.ne.jp/chaichanPaPa/20080802/1217660826

SUZUKI Norio, Jperl
http://homepage2.nifty.com/kipp/perl/jperl/

WATANABE Hirofumi, Jperl
http://www.cpan.org/src/5.0/jperl/
http://search.cpan.org/~watanabe/
ftp://ftp.oreilly.co.jp/pcjp98/watanabe/jperlconf.ppt

Chuck Houpt, Michiko Nozu, MacJPerl
http://habilis.net/macjperl/index.j.html

Kenichi Ishigaki, Pod-PerldocJp, Welcome to modern Perl world
http://search.cpan.org/dist/Pod-PerldocJp/
http://gihyo.jp/dev/serial/01/modern-perl/0031
http://gihyo.jp/dev/serial/01/modern-perl/0032
http://gihyo.jp/dev/serial/01/modern-perl/0033

Fuji, Goro (gfx), Perl Hackers Hub No.16
http://gihyo.jp/dev/serial/01/perl-hackers-hub/001602

Dan Kogai, Encode module
http://search.cpan.org/dist/Encode/
http://www.archive.org/details/YAPCAsia2006TokyoPerl58andUnicodeMythsFactsandChanges (video)
http://yapc.g.hatena.ne.jp/jkondo/ (audio)

Takahashi Masatuyo, JPerl Wiki
http://ja.jperl.wikia.com/wiki/JPerl_Wiki

Juerd, Perl Unicode Advice
http://juerd.nl/site.plp/perluniadvice

daily dayflower, 2008-06-25 perluniadvice
http://d.hatena.ne.jp/dayflower/20080625/1214374293

Unicode issues in Perl
http://www.i-programmer.info/programming/other-languages/1973-unicode-issues-in-perl.html

Jesse Vincent, Compatibility is a virtue
http://www.nntp.perl.org/group/perl.perl5.porters/2010/05/msg159825.html

Tokyo-pm archive
http://mail.pm.org/pipermail/tokyo-pm/
http://mail.pm.org/pipermail/tokyo-pm/1999-September/001844.html
http://mail.pm.org/pipermail/tokyo-pm/1999-September/001854.html

Error: Runtime exception on jperl 5.005_03
http://www.rakunet.org/tsnet/TSperl/12/374.html
http://www.rakunet.org/tsnet/TSperl/12/375.html
http://www.rakunet.org/tsnet/TSperl/12/376.html
http://www.rakunet.org/tsnet/TSperl/12/377.html
http://www.rakunet.org/tsnet/TSperl/12/378.html
http://www.rakunet.org/tsnet/TSperl/12/379.html
http://www.rakunet.org/tsnet/TSperl/12/380.html
http://www.rakunet.org/tsnet/TSperl/12/382.html

ruby-list
http://blade.nagaokaut.ac.jp/ruby/ruby-list/index.shtml
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/2440
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/2446
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/2569
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/9427
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/9431
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/10500
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/10501
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/10502
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/12385
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/12392
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/12393
http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-list/19156

Object-oriented with Perl
http://www.freeml.com/perl-oo/486
http://www.freeml.com/perl-oo/487
http://www.freeml.com/perl-oo/490
http://www.freeml.com/perl-oo/491
http://www.freeml.com/perl-oo/492
http://www.freeml.com/perl-oo/494
http://www.freeml.com/perl-oo/514

To install Char::Latin2, copy and paste the appropriate command in to your terminal.

cpanm

cpanm Char::Latin2

CPAN shell

perl -MCPAN -e shell
install Char::Latin2

For more information on module installation, please visit the detailed CPAN module installation guide.

	Global
`s`	Focus search bar
`?`	Bring up this help dialog

	GitHub
`g` `p`	Go to pull requests
`g` `i`	go to github issues (only if github is preferred repository)

	POD
`g` `a`	Go to author
`g` `c`	Go to changes
`g` `i`	Go to issues
`g` `d`	Go to dist
`g` `r`	Go to repository/SCM
`g` `s`	Go to source
`g` `b`	Go to file browse

	Search terms
module: (e.g. module:Plugin)
distribution: (e.g. distribution:Dancer auth)
author: (e.g. author:SONGMU Redis)
version: (e.g. version:1.00)