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copied!<p>In this case, there is <strong>no need</strong> to use the string form of <code>eval</code> (or any form for that matter). Not only is it slow, but it also can silently trap errors and could lead to untrusted code execution if used with a tainted input. To write a virtual function call in Perl, you can either work with the symbol table directly, or use a symbolic reference:</p> <pre><code>use 5.010; use warnings; use strict; {package HashValidator; sub test_ok {exists $_[0]{ok}} sub test_fail {exists $_[0]{fail}} } my $hashref = {ok => 1}; my $errors; for my $vFunction qw(test_ok test_fail) { # to call the function: say "glob deref: $vFunction: ", $HashValidator::{$vFunction}->($hashref); {no strict 'refs'; say "symbolic: $vFunction: ", &{"HashValidator::$vFunction"}($hashref)} # to conditionally use the result (if it is a true boolean value): if (my $ret = $HashValidator::{$vFunction}->($hashref)) { push @$errors, $ret; } # or to keep the function call in list context: push @$errors, grep $_, $HashValidator::{$vFunction}->($hashref); # or to golf it: push @$errors, $HashValidator::{$vFunction}->($hashref) || (); } say @$errors.': ', join ', ' => @$errors; </code></pre> <p>which prints:</p> <pre><code>glob deref: test_ok: 1 symbolic: test_ok: 1 glob deref: test_fail: symbolic: test_fail: 3: 1, 1, 1 </code></pre> <p>If you are working with object oriented code, virtual method calls are even easier, with no symbol table or symbolic references:</p> <pre><code>$obj->$vMethod(...) </code></pre>

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