Naive Latest.pm implementation using Devel::Declare

Latest.pm

package Latest;

use strict;
use warnings;
use Devel::Declare ();

my $keyword = 'latest';

sub import {
 my $class = shift;

 my $caller = caller;

 Devel::Declare->setup_for(
     $caller,
     { $keyword => { const => \&parser } }
 );
 no strict 'refs';
 *{$caller.'::'.$keyword} = sub (@) {return @_};

}

sub parser {

 my $linestr = Devel::Declare::get_linestr;
 warn "Parser got: $linestr";

 die "Too confusing" if do {
   my @ops = $linestr =~ /(latest)/g;
   @ops > 1;
 };

 if ($linestr =~ /(\$\w+)->/) {
   my $latest = $1;
   $linestr =~ s/latest/latest $latest/;
   warn "Rewritten: $linestr";
   Devel::Declare::set_linestr($linestr);
 } else {
   warn "Could not find keyword";
 }

}

1;

__END__

use example:

#!/usr/bin/env perl

use strict;
use warnings;

use Latest;
use PDL;

my $pdl = xvals(7);

my $where = $pdl->where(latest > 3);

print $where