##################################
# complain.pl  - find what's wrong with others' code fast!
# input should come from STDIN.
# options: --plugin <name> - use the named plugin
#          --verbose - display some stuff

use strict;
use warings;
use Linux; use Mozilla; # OK, ommit this one :-)

# General tool stuff
use Getopt::Long;
my @plugins;
my $verbose;
GetOptions('plugin=s' => \@plugins, 'verbose' => \$verbose);

# Get input program.
my $snippet = eval {local $/; return < >};
print $snippet if $verbose;

##</code><code>##

foreach (@plugin_list) {
    require $_ or warn "Plugin $_ failed to load";
}

##</code><code>##

# Load plugins
@plugins = grep {
    eval{require "plugins/$_.pl"} ? 1 : (warn("Plug-in $_ failed to load.\n"), 0)
} @plugins;

##</code><code>##

require Acme::Current;
# or
use Acme::Current;

##</code><code>##

use Module LIST;
require EXPR;

##</code><code>##

foreach (@plugin_list) {
    $_->init;
}

##</code><code>##

# Do the stuff
foreach (@plugins) {
    $_->evaluate($snippet);
}

##</code><code>##

# Initialization:
foreach (@plugins) {
    $_->init if UNIVERSAL::can($_, 'init');
}

##</code><code>##

#############################
#  plugins/bench.pl

package bench;
use Benchmark;

sub evaluate {
    my $pkg = shift;
    my $snippet = shift;
    print timestr(timeit(400000, $snippet)), "\n";
}
1;

##</code><code>##

 $ ./complain.pl -p bench < snippet.txt

##</code><code>##

package Context;

my %versions = ();

# The returned hash will store for each plugin the complaints it registers.
sub new {
    my $class = shift;
    return bless {}, $class;
}

# This will be optional.
sub declareVersion {
    my $self = shift;
    my ($plugin, $version) = @_;

    $versions{$plugin} = $version;
}

# That's for our program
sub getVersion {
    shift;
    $versions{shift()}
}

# This is how the plugin will tell us what he thinks, as many
# times as it wants to.
sub addOpinion {
    my $self = shift;
    my ($plugin, $opinion) = @_;

    $self->{$plugin} = [] unless exists $self->{$plugin};
    push @{$self->{$plugin}}, $opinion;
}

##</code><code>##

# Start a new context;
my $ctx = Context->new;

# Initialization:
foreach (@plugins) {
    $_->init($ctx) if UNIVERSAL::can($_, 'init');
}

# Do the stuff
foreach (@plugins) {
    $_->evaluate($ctx, $snippet);
}

##</code><code>##

sub evaluate {
    my $pkg = shift;
    my ($ctx, $snippet) = @_;
    $ctx->addOpinion($pkg, timestr(timeit(400000, $snippet)));
}

##</code><code>##


# Simple output.
while (my ($plugin, $opinions) = each %$ctx) {
    my $ver = undef;
    my $verstr = ($ver = Context->getVersion($plugin)) ?
        "(Version $ver) " : '';
    print "The plugin $plugin ${verstr}says:\n";
    print join '\n', map { "\t$_\n" } @$opinions;
}

##</code><code>##

###############################
#  plugins/grammar.pl


package grammar;

sub init {
    my $pkg = shift;
    my $ctx = shift;

    $ctx->declareVersion($pkg, '0.1');
}

sub evaluate {
    my $pkg = shift;
    my ($ctx, $snippet) = @_;

    if ($snippet =~ /use\s+strict;/) {
        $ctx->addOpinion($pkg, "Uses strict. OK");
    } else {
        $ctx->addOpinion($pkg, "Does not use strict; Heathen swine!!");
    }
}

1;

##</code><code>##

perl -e'$b=unpack"b*",pack"H*","59dfce2d6b1664d3b26cd9969503";\
for(;$a<length$b;$a+=9){print+pack"b8",substr$b,$a,8;}'