module type S = Immediate_option_intf.SAlways immediate.
module type S_plain = Immediate_option_intf.S_plainmodule type S_int63 = Immediate_option_intf.S_int63Immediate only on 64-bit machines.
module type S_int63_plain = Immediate_option_intf.S_int63_plainmodule type S_without_immediate = Immediate_option_intf.S_without_immediateNever immediate.