If this is run in a safe environment an easy way to eval the code without it actually running could be to put into a closure (this technique is done by HTML::Mason, which can load a component separately from executing it): 
eval "sub { $code }";
die "Compilation failure: $@" if $@;

[download]
Of course this simple piece of code could be improved, since a comment at the end of $code could break things. 
my $closure = eval "sub {\n$code\n}";

[download]
You call then invoke &$closure (or $closure->()) when you want to actually execute the code. 

--
integral, resident of freenode's #perl

In reply to Re: run-time syntax checking by integral
in thread run-time syntax checking by Pardus

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