in reply to Re^6: Undefined vs empty string
in thread Undefined vs empty string

How very strange.

The upgrading to utf has required the inspection of the bytes and conversion where necessary: 

C:\test\perl -MDevel::Peek -e"utf8::upgrade( $x = qq[abc\xee] ); Dump(
+$x);"
SV = PV(0xea240) at 0x275898
  REFCNT = 1
  FLAGS = (POK,pPOK,UTF8)
  PV = 0xef178 "abc\303\256"\0 [UTF8 "abc\x{ee}"]
  CUR = 5
  LEN = 6

[download]

The original 4-bytes has been converted to (CUR=) 5, which implies (to me at least) that it could have recorded the charwise length at that point rather than having to rediscover it later.

(Also, what shell are you using that allows double quotes embedded within double quotes unescaped?)

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