I have the situation where I have to evaluate an expression which is stored in a variable.

Example:

my $output;
my $expression = "5 < 7";
my $true  = "String displayed if true";
my $false = "String displayed if false";

if (eval($expression)) {
   $output = $true;
} else {
   $output = $false;
}

print $output;

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$expression, $true and $false are all dynamic. This code will be used in a web-environment so eval($expression) is a very bad way to do it.

Is there a secure way to evaluate $expression without use of eval ?

In reply to securely evaluating an expression by Len

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