Test default serializer: obj.to_string(standard)=0.5 Test default serializer with custom userdata: obj.to_string(userdata)=0.5 Test explicit serializer with custom userdata: obj.to_string(custom)=test Test reset serializer: obj.to_string(reset)=0.5 Test no zero reset serializer: obj.to_string(reset)=3.1415000000000002 obj.to_string(default format)=0.52381 obj.to_string(with global format)=x0.524y obj.to_string(with thread format)=T0.52X obj.to_string(long thread format)=Ttttttttttttt0.52xxxxxxxxxxxxxxxxxxX obj.to_string(back to global format)=x0.524y obj.to_string(back to default format)=0.52381 obj(12.0).to_string(default format)=12.0 obj(12.0).to_string(%.0f)=12 obj(12.0).to_string(%.0g)=1e+01 obj(12.0).to_string(%.1g)=12.0 obj(-12.0).to_string(default format)=-12.0 obj(0.0/0.0)=NaN obj(1.0/0.0)=Infinity obj(-1.0/0.0)=-Infinity