Text::MeCab with libmecab < 0.90

libmecab < 0.90 (debianのaptとかは0.80）は内部構造がだいぶ違ってエラーになる罠：

 ./Build
lib/Text/MeCab.xs -> lib/Text/MeCab.c
/usr/bin/perl "-I/usr/lib/perl/5.8" "-I/usr/share/perl/5.8" "/usr/share/perl/5.8/ExtUtils/xsubpp" -noprototypes -typemap "/usr/share/perl/5.8/ExtUtils/typemap" "lib/Text/MeCab.xs"cc -I/usr/lib/perl/5.8/CORE -fPIC -c -D_REENTRANT -D_GNU_SOURCE -DTHREADS_HAVE_PIDS -DDEBIAN -fno-strict-aliasing -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -o lib/Text/MeCab.o lib/Text/MeCab.c
MeCab.xs: In function `init_constants':
MeCab.xs:44: error: `MECAB_NOR_NODE' undeclared (first use in this function)
MeCab.xs:44: error: (Each undeclared identifier is reported only once
MeCab.xs:44: error: for each function it appears in.)
MeCab.xs:45: error: `MECAB_UNK_NODE' undeclared (first use in this function)
MeCab.xs:46: error: `MECAB_BOS_NODE' undeclared (first use in this function)
MeCab.xs:47: error: `MECAB_EOS_NODE' undeclared (first use in this function)
MeCab.xs: In function `XS_Text__MeCab__Node_rlength':
MeCab.xs:228: error: structure has no member named `rlength'
MeCab.xs: In function `XS_Text__MeCab__Node_enext':
MeCab.xs:286: error: structure has no member named `enext'
MeCab.xs:289: error: structure has no member named `enext'
MeCab.xs: In function `XS_Text__MeCab__Node_bnext':
MeCab.xs:307: error: structure has no member named `bnext'
MeCab.xs:310: error: structure has no member named `bnext'
MeCab.xs: In function `XS_Text__MeCab__Node_rcattr':
MeCab.xs:348: error: structure has no member named `rcAttr'
MeCab.xs: In function `XS_Text__MeCab__Node_lcattr':
MeCab.xs:359: error: structure has no member named `lcAttr'
MeCab.xs: In function `XS_Text__MeCab__Node_isbest':
MeCab.xs:381: error: structure has no member named `isbest'
MeCab.xs: In function `XS_Text__MeCab__Node_alpha':
MeCab.xs:392: error: structure has no member named `alpha'
MeCab.xs: In function `XS_Text__MeCab__Node_beta':
MeCab.xs:403: error: structure has no member named `beta'
MeCab.xs: In function `XS_Text__MeCab__Node_prob':
MeCab.xs:414: error: structure has no member named `prob'
MeCab.xs: In function `XS_Text__MeCab__Node_wcost':
MeCab.xs:426: error: structure has no member named `wcost'
error building .o file from 'lib/Text/MeCab.c' at /usr/local/share/perl/5.8.4/Module/Build/Base.pm line 2534.

報告by miyagawaさん。0.80と0.90ではだいぶ内部構造に差があるらしい。これ、Build.PLからprobe_mecab.plってのを呼んで、バージョン情報をclibsに渡す事で回避することにする：

  # Build.PL
  my $result = do 'probe_mecab.pl'

probe_mecab.plはこんな感じ（あとでModule::Buildへの依存をなくす）：

use strict;
use File::Spec;
use Module::Build;

# try probing in places where we expect it to be

my $mecab_config;

foreach my $path qw(/usr/bin /usr/local/bin) {

    my $tmp = File::Spec->catfile($path, 'mecab-config');

    if (-f $tmp && -x _) {

        $mecab_config = $tmp;

        last;

    }

}

if (my $tmp = Module::Build->prompt("Path to mecab config? [$mecab_config]")) {

    $mecab_config = $tmp;

}

if (!-f $mecab_config || ! -x _) {

    print STDERR "Can't proceed without mecab-config. Aborting...\n";

    exit 1;

}

my $version = `$mecab_config --version`;

chomp $version;

print "detected mecab version $version\n";

if ($version < 0.90) {

    print " + mecab version < 0.90 doesn't contain some of the features\n",

          " + that are available in Text::MeCab. Please read the documentation\n",

          " + carefully before using\n";

}

my($major, $minor, $micro) = split(/\./, $version);

my $cflags = `$mecab_config --cflags`;

chomp($cflags);

$cflags .= " -DMECAB_MAJOR_VERSION=$major -DMECAB_MINOR_VERSION=$minor";

print "Using compiler flags '$cflags'...\n";

my $libs   = `$mecab_config --libs`;

chomp($libs);

print "Using linker flags '$libs'...\n";

return { cflags => $cflags, libs => $libs };

で、実際のコンパイルするときは、こんな感じでpreprocessorレベルでコードを変更：

#if MECAB_MAJOR_VERSION > 1 || MECAB_MINOR_VERSION >= 0.90

  ... 0.90以降に使える機能 ...

#endif

なんかあとで細かく見るので0.03は明日あたりにリリース予定。