Using row_to_json with %ROWTYPE ?

Hi,

I have a function that broadly looks like this :

create function doStuff() returns json as $$
DECLARE
v_row my_view%ROWTYPE;
BEGIN
select * into strict v_row from my_view where foo=bar;
select row_to_json(v_row) from v_row;
END;
$$ LANGUAGE plpgsql;


However this does not seem to work ?   What am I doing wrong ?

Thanks

Tim