The bug is not "accent in variable" The bug is that in second eval the perl lexer can't parse normal variable anymore...Eval is useful to execute buggy code ... that's why i use it, because the code comes from user and he can always put "Unrecognized character"

And your are rigth , the way to solve the bug "accent in variable" is this way :

 
use Unicode::String; 
my $code1='my $var_with_é_accent=5;print "var is $var_with_é_accent";'
+;
$code1="use utf8;$code1";
$code1=Unicode::String::latin1($code1)->utf8;

print "\nEval buggy code\n";
eval "$code1"; 
print "ERR = $@" if ($@);;
print "DONE\n";

my $string;
my $code2='$string="new eval done";';

print "\nEval good code\n";
eval $code2;

print "ERR = $@" if ($@);
print "string is : $string\n";
print "DONE\n";
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The bug exists with use utf8 too.

use strict;
use warnings;

use Encode         qw( encode          );
use HTML::Entities qw( decode_entities );

# This eval should have no effect on subsequent evals.
eval encode('utf-8', decode_entities(
   'use utf8; my $var_with_♥_non_word;'
));

my $string = 'abc';
eval '$string = "def"; 1' or die;
if ($string ne 'def') {
   print("BUG! string should be 'def' but is '$string'\n");
} else {
   print("No bug\n");
}
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BUG! string should be 'def' but is 'abc'
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