add missing lazy evaluation stuff
add missing lazy evaluation stuff

elen4/simbody,chrisdembia/simbody,chrisdembia/simbody,elen4/simbody,robojukie/simbody,Gjacquenot/simbody,robojukie/simbody,simbody/simbody,elkingtonmcb/simbody,scamille/simbody,Gjacquenot/simbody,chrisdembia/simbody,scamille/simbody,elkingtonmcb/simbody,scamille/simbody,robojukie/simbody,elkingtonmcb/simbody,Gjacquenot/simbody,simbody/simbody