Quoting is not an identity function in Perl.

It's not, but if you're going to use them as hash keys, they get quoted anyway: 

perl -MDevel::Peek -e '$a = 1; Dump ($a); %a = map +{$_}, $a; Dump ($a
+)'
SV = IV(0x8192edc) at 0x8191dc4
  REFCNT = 1
  FLAGS = (IOK,pIOK)
  IV = 1
SV = PVIV(0x8184888) at 0x8191dc4
  REFCNT = 1
  FLAGS = (IOK,POK,pIOK,pPOK)
  IV = 1
  PV = 0x818b5b8 "1"\0
  CUR = 1
  LEN = 2

[download]

perl -MDevel::Peek -e '$a = 1; Dump ($a); %a = map {"$_",}, $a; Dump (
+$a)'
SV = IV(0x8192edc) at 0x8191dc4
  REFCNT = 1
  FLAGS = (IOK,pIOK)
  IV = 1
SV = PVIV(0x8184888) at 0x8191dc4
  REFCNT = 1
  FLAGS = (IOK,POK,pIOK,pPOK)
  IV = 1
  PV = 0x818b5b8 "1"\0
  CUR = 1
  LEN = 2

[download]
No difference.

In reply to Re^6: Perl oddities by Anonymous Monk
in thread Perl oddities by brian_d_foy

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