% doreturn - Do an action and then return some other value
%
% doreturn :: (void=>A), B => B.
% doreturn :: (void=>A), B1, ..., BN => B1, ..., BN. 
%
% This is useful when you need to construct an action expression
% using sub actions that return no value.
function varargout=doreturn(a,varargin), a(); varargout=varargin;

