Rework select function to be lazy
Rework select function to be lazy

pombredanne/pythran,artas360/pythran,pombredanne/pythran,serge-sans-paille/pythran,pbrunet/pythran,pbrunet/pythran,hainm/pythran,artas360/pythran,serge-sans-paille/pythran,hainm/pythran,hainm/pythran,pombredanne/pythran,artas360/pythran,pbrunet/pythran