File Coverage

blib/lib/Data/Unixish/tail.pm

Criterion	Covered	Total	%
statement	23	23	100.0
branch	2	2	100.0
condition	2	2	100.0
subroutine	6	6	100.0
pod	1	1	100.0
total	34	34	100.0

package Data::Unixish::tail;

use 5.010;
use strict;
use syntax 'each_on_array'; # to support perl < 5.12
use warnings;
#use Log::Any '$log';

our $VERSION = '1.572'; # VERSION

use Data::Unixish::Util qw(%common_args);

our %SPEC;

$SPEC{tail} = {
    v => 1.1,
    summary => 'Output the last items of data',
    args => {
        %common_args,
        items => {
            summary => 'Number of items to output',
            schema=>['int*' => {default=>10}],
            tags => ['main'],
            cmdline_aliases => { n=>{} },
        },
    },
    tags => [qw/filtering/],
};
sub tail {
    my %args = @_;
    my ($in, $out) = ($args{in}, $args{out});
    my $n = $args{items} // 10;

    # maintain temporary buffer first
    my @buf;

    while (my ($index, $item) = each @$in) {
        push @buf, $item;
        shift @buf if @buf > $n;
    }

    # push buffer to out
    push @$out, $_ for @buf;

    [200, "OK"];
}

1;
# ABSTRACT: Output the last items of data

__END__