#!/usr/bin/env perl

# http://www.perl.com/pub/2012/04/perlunicook-standard-preamble.html
use utf8;      # so literals and identifiers can be in UTF-8
use v5.12;     # or later to get "unicode_strings" feature
use strict;    # quote strings, declare variables
use warnings;  # on by default
use warnings  qw(FATAL utf8);    # fatalize encoding glitches
use open      qw(:std :utf8);    # undeclared streams in UTF-8
use charnames qw(:full :short);  # unneeded in v5.16

use Dancer;

use Encode ();
use HTML::Entities ();
use JSON::XS ();
use Devel::Peek;
use utf8;

our $string = "Hello – World";

get '/' => sub {
    return '<a href="/ok">ok</a> <a href="/crash">crash</a>';
};

get '/ok' => sub {
    my $perl_internal = Encode::decode('utf-8', $string);    # "use ut
+f8;" above made $string be in utf-8, decode to Perl-internal (= Unico
+de, stored internally as utf-8, right?)
    HTML::Entities::decode_entities($perl_internal);    # in void cont
+ext, expand entities in-place to Unicode
    my $json = JSON::XS::encode_json([$perl_internal]);    # pass a Pe
+rl data structure, and expect output to be a utf-8 encoded, binary st
+ring

    Dump( $perl_internal );
    Dump( $json );

    my $ok = utf8::decode($json);                # fairly good way to 
+validate utf-8

    return "JSON:$json <br>". ($ok ? "ok" : "not ok");
};

get '/crash' => sub {
    my $perl_internal = Encode::decode('utf-8', $string);
    HTML::Entities::decode_entities($perl_internal);
    my $json = to_json([$perl_internal],{pretty => 0});    # JSON's to
+_json, in contrary to JSON::XS's to_json seems to do something wrong,

    Dump( $perl_internal );
    Dump( $json );
                                # or is less clever in automagically h
+andling what I'm doing wrong while preparing the scalar
    my $ok = utf8::decode($json);

    return "JSON:$json <br>". ($ok ? "ok" : "not ok");
};
 
dance;
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