Slightly OT, but probably worth mentioning. Eval is indeed cool, but it has its evil side. E.g the following code:

#code a
my $function = $node->{'activationfunction'};
my $functionCall ="\$value = \$network->$function(\$value);";
eval($functionCall);

#code b

my $function = $node->{'activationfunction'};
$value = $network->$function($value);

[download]

Eval saved me once upon a time from having to learn that code b was possible. BUT, since I was calling this tens of thousands of times in normal program execution, and hence invoking the compiler every time, once I did learn that code b was possible, the program speeded up by several hundred fold!

The moral - eval is cool, but very very slow!

g0n, backpropagated monk

In reply to Re: eval inside an object by g0n
in thread eval inside an object by Angel

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