I think you're going to be disappointed. You can't just take a result and get the function that generated that result or, for that matter, even get the variable name associated with a give variable. One way would be to store variable names in variables, combine them at will and eval the result. Personally, I think this will cause you grief, though.

my $bad_idea1 = '$var1';
my $bad_idea2 = '$var2';

my $var1 = 3;
my $var2 = 4;

my $equation = "$bad_idea1 + $bad_idea2";
print "$equation\n";
print eval $equation;
[download]

Here's an example of how things can go wrong:

my $bad_idea1 = '$var1';
my $bad_idea2 = '$var2';

my $var1 = 3;
my $var2 = 0;

my $equation = "$bad_idea1 / $bad_idea2";
print "$equation\n";
my $result = eval $equation;
if ( $@ ) {
    print $@;
} else {
    print $result;
}
[download]

Cheers,
Ovid

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