Section Composition.
Variables L1 L2 L3: semantics.
Variable get_mem1: state L1 -> mem.
Variable get_mem2: state L2 -> mem.
Variable get_mem3: state L3 -> mem.

Lemma injection_extension_composition:
@fsim_properties_inj L1 L2 get_mem1 get_mem2 ->
@fsim_properties_ext L2 L3 get_mem2 get_mem3 ->
@fsim_properties_inj L1 L3 get_mem1 get_mem3.