param a=1.
param y=1.
param b={ '{1,2,a} }
eval b
param c={ '{exp(1),2,exp(a)} }
eval c
param
param d=" '{1,2,a, '{exp(a),y,exp(z)}, 0. } "
eval d
param e=" '{1,2,b, '{b,b}, 0. } "
eval e