perl - 如何在 pod2usage 中指定宽度？

Question

我有一个小的 perl 模块，并且正在使用 Getopt::Long，我想我不妨使用 Pod::Usage 来获得一个漂亮的帮助显示。

经过一番摆弄，我让它工作得相当好，只有一个小异常(exception)。我无法设置输出的宽度。

我的终端有 191 个字符宽。使用 perldoc Module.pm，它将文档正确格式化为该宽度。使用 pod2usage()，它使用 76 个字符的默认宽度。

我不知道如何将宽度选项传递给格式化程序。该文档显示了如何使用 BEGIN block 设置不同的格式化程序(例如 Pod::Text::Termcap)，并且我使用 Term::ReadKey 来拉宽度(已验证)，但我无法让格式化程序看见。

有什么提示吗？

这是我要测试的完整模块，以及一个用于加载它的小测试脚本。要明白我的意思，打开一个具有合理宽度的终端(132 或更大，所以很明显)，并将“./test.pl --man”的输出与“perldoc MUD::Config”的输出进行比较.

我可以不用 perldoc 添加的手册页样式页眉和页脚，但我希望它尊重(并使用)终端宽度。

测试.pl

#!/usr/bin/perl -w

use strict;
use warnings;

use MUD::Config;
#use MUD::Logging;

my $config = new MUD::Config @ARGV;
#my $logger = new MUD::Logging $config;

#$bootlog->info("Logging initialized");
#$bootlog->info("Program exiting");

和 MUD/Config.pm

#!/usr/bin/perl -w

package MUD::Config;

=pod

=head1 NAME

MUD::Config --  Configuration options for PocketMUD

=head1 SYNOPSIS

./PocketMUD [OPTIONS]

=head1 OPTIONS

=over 8

=item B<--dbname>

Specifiy the name of the database used by PocketMUD S<(default B<pocketmud>)>.

=item B<--dbhost>

Specify the IP address used to connect to the database S<(default B<localhost>)>.

=item B<--dbport>

Specify the port number used to connect to the database S<(default B<5432>)>.

=item B<--dbuser>

Specify the username used to connect to the database S<(default B<quixadhal>)>.

=item B<--dbpass>

Specify the password used to connect to the database S<(default B<password>)>.

=item B<--dsn>

The DSN is the full connection string used to connect to the database.  It includes the
values listed above, as well as several other options specific to the database used.

S<(default B<DBI:Pg:dbname=$db_name;host=$db_host;port=$db_port;sslmode=prefer;options=--autocommit=on>)>

=item B<--logfile>

Specify the text file used for debugging/logging output S<(default B</home/quixadhal/PocketMUD/debug-server.log>)>.

=item B<--port>

Specify the port used for player connections S<(default B<4444>)>.

=item B<--help>

Display usage information for PocketmUD.

=item B<--man>

Display full documentation of configuration module details.

=back

=head1 DESCRIPTION

PocketMUD is a perl re-implementation of SocketMUD.

It is meant to be a barebones MUD server, written in perl,
which can be easily modified and extended.

=head1 METHODS

=cut

use strict;
use warnings;
use Getopt::Long qw( GetOptionsFromArray );
use Config::IniFiles;
use Data::Dumper;

BEGIN {
    use Term::ReadKey;

    my ($width, $height, $pixel_width, $pixel_height) = GetTerminalSize();
    #print "WIDTH: $width\n";
    $Pod::Usage::Formatter = 'Pod::Text::Termcap';
    $Pod::Usage::width = $width;
}

use Pod::Usage;
use Pod::Find qw(pod_where);

Getopt::Long::Configure('prefix_pattern=(?:--|-)?');    # Make dashes optional for arguments

=pod

B<new( @ARGV )> (constructor)

Create a new configuration class.  You should only need ONE instance of this
class, under normal circumstances.

Parameters passed in are usually the command line's B<@ARGV> array.  Options that
can be specified are listed in the B<OPTIONS> section, above.

Returns: configuration data object.

=cut


sub new {
    my $class = shift;
    my @args = @_;
    my ($db_name, $db_host, $db_port, $db_user, $db_pass, $DSN);
    my ($logfile, $port);
    my $HOME = $ENV{HOME} || ".";

    # Order matters... First we check the global config file, then the local one...
    foreach my $cfgfile ( "/etc/pocketmud.ini", "$HOME/.pocketmud.ini", "./pocketmud.ini" ) {
        next if !-e $cfgfile;
        my $cfg = Config::IniFiles->new( -file  => "$cfgfile", -handle_trailing_comment => 1, -nocase => 1, -fallback => 'GENERAL', -default => 'GENERAL' );
        $db_name = $cfg->val('database', 'name')        if $cfg->exists('database', 'name');
        $db_host = $cfg->val('database', 'host')        if $cfg->exists('database', 'host');
        $db_port = $cfg->val('database', 'port')        if $cfg->exists('database', 'port');
        $db_user = $cfg->val('database', 'user')        if $cfg->exists('database', 'user');
        $db_pass = $cfg->val('database', 'password')    if $cfg->exists('database', 'password');
        $DSN = $cfg->val('database', 'dsn')             if $cfg->exists('database', 'dsn');
        $logfile = $cfg->val('general', 'logfile')      if $cfg->exists('general', 'logfile');
        $port = $cfg->val('general', 'port')            if $cfg->exists('general', 'port');
    }

    # Then we check arguments from the constructor
    GetOptionsFromArray( \@args ,
        'dbname:s'      => \$db_name,
        'dbhost:s'      => \$db_host,
        'dbport:i'      => \$db_port,
        'dbuser:s'      => \$db_user,
        'dbpass:s'      => \$db_pass,
        'dsn:s'         => \$DSN,
        'logfile:s'     => \$logfile,
        'port:i'        => \$port,
        'help|?'        => sub { pod2usage( -input => pod_where( {-inc => 1}, __PACKAGE__), -exitval => 1 ); },
        'man'           => sub { pod2usage( -input => pod_where( {-inc => 1}, __PACKAGE__), -exitval => 2, -verbose => 2 ); },
    );

    # Finally, we fall back to hard-coded defaults
    $db_name = 'pocketmud'  if !defined $db_name and !defined $DSN;
    $db_host = 'localhost'  if !defined $db_host and !defined $DSN;
    $db_port = 5432         if !defined $db_port and !defined $DSN;
    $db_user = 'quixadhal'  if !defined $db_user;
    $db_pass = 'password'   if !defined $db_pass;
    $logfile = '/home/quixadhal/PocketMUD/debug-server.log' if !defined $logfile;
    $port    = 4444         if !defined $port;

    $DSN = "DBI:Pg:dbname=$db_name;host=$db_host;port=$db_port;sslmode=prefer;options=--autocommit=on" if !defined $DSN and defined $db_name and defined $db_host and defined $db_port;

    die "Either a valid DSN or a valid database name, host, and port MUST exist in configuration data" if !defined $DSN;
    die "A valid database username MUST exist in configuration data" if !defined $db_user;
    die "A valid database password MUST exist in configuration data" if !defined $db_pass;
    die "A valid logfile MUST be defined in configuration data" if !defined $logfile;
    die "A valid port MUST be defined in configuration data" if !defined $port;


    my $self = {
        DB_NAME => $db_name,
        DB_HOST => $db_host,
        DB_PORT => $db_port,
        DB_USER => $db_user,
        DB_PASS => $db_pass,
        DSN     => $DSN,
        LOGFILE => $logfile,
        PORT    => $port,
    };

    bless $self, $class;
    print Dumper($self);
    return $self;
}

sub dsn {
    my $self = shift;
    if ( @_ ) {
        $self->{DSN} = shift;
    }
    return $self->{DSN};
}

sub db_user {
    my $self = shift;
    if ( @_ ) {
        $self->{DB_USER} = shift;
    }
    return $self->{DB_USER};
}

sub db_pass {
    my $self = shift;
    if ( @_ ) {
        $self->{DB_PASS} = shift;
    }
    return $self->{DB_PASS};
}

sub logfile {
    my $self = shift;
    if ( @_ ) {
        $self->{LOGFILE} = shift;
    }
    return $self->{LOGFILE};
}

sub port {
    my $self = shift;
    if ( @_ ) {
        $self->{PORT} = shift;
    }
    return $self->{PORT};
}

1;

Answer 1

伙计，我真的在寻找这个挑战......

我偷看了 Pod::Usage 的代码看看发生了什么。 Pod::Usage使用 perldoc直接命令，所以看起来都是 perldoc和 pod2usage将以相同的方式打印。事实上，在我的系统上，perldoc和 pod2usage默认或多或少为 80 列。我不知道为什么它在您的系统上有所不同。

有一个异常(exception):

如果您设置 -noperldoc参数，它将使用 Pod::Text用于格式化和 Pod::Text有一个选项-width => $width当你创建一个新的 Pod::Text目的。

我以为我可以通过一个无证的 -width pod2usage 的参数它会被传递给 $parser被创建的对象。这个对象是 Pod::Usage对象，但 Pod::Usage是 Pod::Text 的子类.

没有骰子。

这些选项作为单独的 USAGE_OPT 的一部分传递。选项，所以 $opt_width未正确设置。 Pod::Text 没有功能接口(interface)，因此宽度与特定的 $parser 相关联对象而不是一般的包。不能设置$Pod::Text::width并覆盖默认 76值(value)。默认情况下，这是在程序中硬编码的。

有一种方法可以使用Pod::Text ，找到一种获取终端宽度的方法，将其传递给您的Pod::Text对象，然后使用该对象调用 parse_from_file对您的源文件执行方法。

如果终端是 130 个字符宽，那么您可以看到 130 个字符宽的 POD 输出，这将是很多工作。