use URL::Encode 'url_decode_utf8';
use utf8::all;
$string = '%E6%88%91%E7%88%B1c++';
print url_decode_utf8("$string");

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It end up with '+' to space, in '/usr/share/perl5/site_perl/URL/Encode/PP.pm' it has code 
 ...
 $EncodeMap{"\x20"} = '+';
 ...
 $s =~ y/+/\x20/;

[download]
It intends to protect '+', but failed to convert it back. comment the two lines on the contrary works fine.

Why all this?

In reply to why URL::Encode deliberately mistreat '+' by vincentaxhe

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