here one pure regex solution using /e eval-option to handle different cases: 
  DB<151> $str=$str0
 => " bla0 \"ignore a1\" bla1 \"ignore a2\" bla2"

  DB<152> $str =~ s/("[^"]*?"|a)/ $1 eq "a" ? "A" : $1 /ge
 => 5

  DB<153> $str
 => " blA0 \"ignore a1\" blA1 \"ignore a2\" blA2"

[download]

Cheers Rolf

( addicted to the Perl Programming Language)

In reply to Re: In place replace, ignoring between quotes (one regex) by LanX
in thread In place replace, ignoring between quotes by Klainn

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