fact: Definition le_ereal x1 x2 := match x1, x2 with | -oo, r%:E | r%:E, +oo => r \is Num.real | r1%:E, r2%:E => r1 <= r2 | -oo, _ | _, +oo => true | +oo, _ | _, -oo => false end.
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra) signed