fact: Definition widen_signed x nz' cond' (unz : unify_nz nz' nz) (ucond : unify_r cond' cond) := Signed.mk (widen_signed_subproof x unz ucond).
imports: HB(structures) Coq(ssreflect ssrfun ssrbool) mathcomp(ssrnat eqtype choice order ssralg ssrnum ssrint) mathcomp(mathcomp_extra)