Even with your misspeak, that's just a bug in Perl. 

use Devel::Peek;;

$a = '';;
$a = chr( 65 );;
Dump $a;;
SV = PV(0x11cfc0) at 0x11f248
  REFCNT = 1
  FLAGS = (POK,pPOK)
  PV = 0x3d6ccc8 "A"\0
  CUR = 1
  LEN = 8

$a .= chr( 2**32 );;
Dump $a;;
SV = PV(0x11cfc0) at 0x11f248
  REFCNT = 1
  FLAGS = (POK,pPOK,UTF8)
  PV = 0x3d6cbd8 "A\376\204\200\200\200\200\200"\0Malformed UTF-8 char
+acter (byte 0xfe) in subroutine entry
 [UTF8 "A\x{0}"]
  CUR = 8
  LEN = 16

[download]

It allows you to construct a malformed utf-8 (unicode) string. It shouldn't.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"I'd rather go naked than blow up my ass"

In reply to Re^33: Interleaving bytes in a string quickly by BrowserUk
in thread Interleaving bytes in a string quickly by BrowserUk

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