$ perl -wle'
    sub make {
        my ($x) = @_;
        return sub {
            eval q{$x};
        };
    }

    print make(123)->()
'
Use of uninitialized value in print at -e line 9.


##</code><code>##

$ perl -wle'
    sub make {
        my ($x) = @_;
        return sub {
            eval q{$x};
        };
    }

    print make(123)->()
'
Variable "$x" is not available at (eval 1) line 2.
Use of uninitialized value in print at -e line 9.


##</code><code>##

$ perl -wle'
    sub make {
        my ($x) = @_;
        return sub {
            $x if 0;      # <--- added
            eval q{$x};
        };
    }

    print make(123)->()
'
123