Perl treats literal numbers differently from strings converted to numbers, and as others have said literals beginning with zero are octal numbers:

$ perl -wMstrict -le 'print 0+"010"'
10
$ perl -wMstrict -le 'print 0+ 010 '
8

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When you write my $x = "016"; $y = eval("$x * 10");, the $x is evaluated into the string before the eval and it is the equivalent of asking Perl to evaluate 016 * 10:

$ perl -wMstrict -le 'my $x = "016"; print eval("$x * 10");'
140
$ perl -wMstrict -le 'print 016 * 10;'
140

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In reply to Re: Leading Zeros confound eval() ? by Anonymous Monk
in thread Leading Zeros confound eval() ? by misterperl

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