The stringified form also depends if the values began as strings or numbers. 

$x = '1e-3'; 
$y = 0.001; 
if ( $x eq $y ) { print "$x and $y are equal.\n" }
else { print "$x and $y are not equal" }

print "\n";

$x = $x + 0;
if ( $x eq $y ) { print "$x and $y are equal.\n" }
else { print "$x and $y are not equal" }

[download]
Result is: 
1e-3 and 0.001 are not equal
0.001 and 0.001 are equal.

[download]

In the first comparison, $x is a string. In the second comparison, $x is numeric before it is stringified for comparison.

The Scalar::Util documentation is useful here. https://perldoc.perl.org/Scalar/Util.html#isdual

In reply to Re^2: Why does this string comparison compares "numerically" and can I rely on this in general? by swl
in thread Why does this string comparison compares "numerically" and can I rely on this in general? by Bloehdian

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