Fair enough. The scalar() version is certainly more efficient, but I think the || undef is more descriptive.

Just to keep this post from having zero value, here's another case where I used B without eval. The problem was to show what a format (set via a complex eval STRING) was getting set to. Original version only allowed deparse_format(*WHATEVER{FORMAT}) but *FOO{FORMAT} isn't supported before perl-5.7.0. 

sub deparse_format {
    use B::Deparse;
    # translate arg (or reference to it) into a B::* object
    my $Bobj = B::svref_2object(ref $_[0] ? $_[0] : \$_[0]);
    # if passed a glob or globref, get the format
    $Bobj = B::GV::FORM($Bobj) if ref $Bobj eq 'B::GV';

    if (ref $Bobj ne 'B::FM') {
        require Carp;
        Carp::croak "deparse_format: expected a glob, globref, or form
+at ref";
    }

    my $deparser = B::Deparse::->new();
    return $deparser->indent($deparser->deparse_format($Bobj));
}

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In reply to Re^5: Good way of handling eval failures and deparsing formats by ysth
in thread Good way of getting subroutine name from ref? by bronson

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