fact: Definition code (x : \bar R) := match x with | r%:E => GenTree.Node 0 [:: GenTree.Leaf r] | +oo => GenTree.Node 1 [::] | -oo => GenTree.Node 2 [::] end.
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap) mathcomp(mathcomp_extra) signed