Hi! First of all, "reval" only evaluates the code and then returns the value. So in this case, the following will work: 
use warnings;
use strict;
use Safe;
use feature qw{say};

say "Hello!";

my $cft = Safe->new;

$cft->deny_only();

my $ret = $dft->reval(qq{return "Hello Again!"}, undef);

say $ret;

[download]
So using the "say" doesn't work because it evaluates to nothing, and returns nothing. In fact, I was kind of surprised that it didn't at least return "1" since say should return "true". But who knows.

Update: something else just occurred to me. Safe is not going to evaluate the "use" or in this case what I tried below. It evaluates the entire script, doesn't recognize the "say" keyword and throws the error. It never *executes* the use or the require/import. 
my $unsafe = qq|
     require feature;
     feature->import( qw{say switch} );
     say "Hope this works";
     return "I did what you said";
|;
# explicit load of feature, but doesn't work (unexpected result)
 
$ret = $cft->reval( $unsafe, undef );

[download]


HTH,
Tyler.

In reply to Re: using features in a Safe compartment by muzakfetch
in thread using features in a Safe compartment by djerius

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