[LT] Regexp, Perl, and Port
id:kdaiba

whoami
id:kdaiba
Erlang newbie
Perl Monger
Yokohama.pm
Shibuya.pm
Tokyo.pm
Now, setting up \"Japan Perl Association\"
http://trac.endeworks.jp/trac/tpfj/wiki
Infrastructure Engineer

Erlang supports unicode in R12B-5

Try to print utf-8
perl -e 'map{printf \"%d,\",$_}(unpack \"C*\",\"寿\");print \"\\n\";'
229,175,191,
1> UniString = [229,175,191].
\"寿\"
2> io:format(\"~p~n\",[UniString]).
\"寿\"
ok
3>
It's looks OK on mac's terminal. But ...

When you run this script...
#!/usr/local/bin/escript
main(_) ->
Item0 = \"寿\",
Item1 = \"寿限\",
Item2 = \"寿限無\",
Item3 = [[229,175,191],[233,153,144],[231,132,161]],
io:format(\"~p~n\", [Item0]),
io:format(\"~p~n\", [Item1]),
io:format(\"~p~n\", [Item2]),
[io:format(\"~p~n\", [X]) || X <- Item3].

You'll get returns, like below
\"寿\"
[229,175,191,233,153,144]
[229,175,191,233,153,144,231,132,161]
\"寿\"
[233,153,144]
[231,132,161]

Do google
There is a page,
\"Representing Unicode characters in Erlang\"
http://www.erlang.org/eeps/eep-0010.html
It's a \"Erlang Enhancement Proposals (EEPs)\", #10
This proposal's STATUS
http://www.erlang.org/eeps/
Standards Track EEP
Accepted proposal
NOT \"Proposal is implemented in OTP release R12B-5\"

Can't I use utf-8 now ?
use Erlang::Port to see Unicode

I made a perl script to printout utf-8
#!/usr/local/bin/escript
main(_) ->
perlsay:start(\"./perlsay.pl\"),
perlsay:say(\"寿限無、寿限無、五劫の擦り切れ、海砂利水魚、水
行末、雲来末、風来末、食う寝る所に住む所、薮ら柑子のぶら柑子、
パイポ、パイポ、パイポのシューリンガン、シューリンガンのグーリンダ
イ、グーリンダイのポンポコピーのポンポコナーの長久命の長助\"),
perlsay:stop().

You'll get returns on STDERR
寿限無、寿限無、五劫の擦り切れ、海砂利水魚、水行末、雲来末、
風来末、食う寝る所に住む所、薮ら柑子のぶら柑子、パイポ、パイ
ポ、パイポのシューリンガン、シューリンガンのグーリンダイ、グーリン
ダイのポンポコピーのポンポコナーの長久命の長助

Easy erlang code and
-module(perlsay).
-export([say/1]).
-export([start/1, stop/0]).
-import(perlport, [call/2, stop/1]).
say(String) ->
call([say, String], perlsay).
start(Script) ->
perlport:start(Script, perlsay).
stop() ->
perlport:stop(perlsay).

Spaghetti perl script (1/4)
#!/usr/local/bin/perl
package Erlang::Port::Say;
use strict;
use warnings;
use Erlang::Port;
caller or __PACKAGE__->main(@ARGV);
1;

Spaghetti perl code (2/4)
sub main {
my $pkg = shift;
Erlang::Port->new(
sub {
my $obj = shift;
my $port = shift;
my $ret = eval { _my_proc( $obj, $port ) };
$ret = $port->_newTuple( [ $port->_newAtom('error') => $@, ] )
if ($@);
$ret;
}
)->loop();
}

Spagetti perl Script (3/4)
sub _my_proc {
my $obj = shift;
my $port = shift;
if ( !UNIVERSAL::isa( $obj, 'ARRAY' ) ) {
return $port->_newTuple( [ $port->_newAtom('badarg'), $obj ] );
}
my $key = _to_s( $obj->[0] );
if ( !defined($key) || $key ne 'say' ) {
return $port->_newTuple( [ $port->_newAtom('badarg'), $obj ] );
}
my $str = _to_s( $obj->[1] );
if ( !defined($str) ) {
return $port->_newTuple( [ $port->_newAtom('badarg'), $obj ] );
}
print STDERR $str, \"\\n\";
$str;
}

Spagetti Perl Script (4/4)
sub _to_s {
my $obj = shift;
if ( defined($obj) && !ref($obj) ) {
$obj;
}
elsif ( $obj && ref($obj) eq 'ARRAY' && @$obj == 0 ) {
\"\";
}
elsif ( ref($obj) && UNIVERSAL::isa( $obj, 'Erlang::Atom' ) ) {
$$obj;
}
elsif ( ref($obj) && UNIVERSAL::isa( $obj, 'Erlang::Binary' ) ) {
$$obj;
}
else { undef; }
}

\"song and dance\" too long ?
I'm sorry to be boring

You can use this code like this
#!/usr/local/bin/escript
main(_) ->
perlre:start(\"./perlre.pl\"),
perlsay:start(\"./perlsay.pl\"),
F = perlre:match(\"赤とんぼ\",\"(\\\\p{Hiragana}+)\"),
[perlsay:say(X) || X <- F],
perlre:stop(),
perlsay:stop().
# perlre.pl is a sample code of Erlang::Port

Finally, you get ...
とんぼ

Twist ending
I need to check B12-R5
Today I have bad feelings. So I download B12-R5. It shows,
Eshell V5.6.5 (abort with ^G)
But, when I check my mac's erl, it shows
Eshell V5.6.4 (abort with ^G)
I made a mumbo jumbo ....