#! /usr/bin/perl
use warnings;
use strict;

use Time::Piece;

{   package My;
    use Moo;
    use Time::Piece;

    sub is_date {
        my ($date) = @_;
        die "Wrong type" unless shift->isa('Time::Piece');
    }
    use namespace::clean;

    has time_piece  => (is => 'rw', isa => \&is_date);
    has string_date => (
        is => 'rw',
        coerce => sub { my $tp = shift;
                        $tp = 'Time::Piece'->strptime($tp, '%Y%m%d')
                            unless $tp->isa('Time::Piece');
                        return $tp
                    },
        isa => \&is_date);
}

my $now = localtime;
my $o = 'My'->new( time_piece  => $now,
                   string_date => '20170911' );

eval { $o->string_date($now) }      or warn "1: $@"; # works
eval { $o->string_date('a') }       or warn "2: $@"; # coercion for "s
+tring_date" failed: Error parsing time
eval { $o->time_piece('20170911') } or warn "3: $@"; # isa check for "
+time_piece" failed: Wrong type
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($q=q:Sq=~/;[c](.)(.)/;chr(-||-|5+lengthSq)`"S|oS2"`map{chr |+ord
}map{substrSq`S_+|`|}3E|-|`7**2-3:)=~y+S|`+$1,++print+eval$q,q,a,
[download]