X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=matita%2Fdama%2Ftopology.ma;h=f068fcbd56bc79c914740bc9752c0e14bcef6dcb;hb=a3f4c0a8b4328cb9a9fe3b4c2e577be2a258675c;hp=e0a926d7673ebbbcdaf9ce8fd5582e3857a5c401;hpb=b838d48720ddee4e514d1718b1cf9d90350a1f0e;p=helm.git diff --git a/matita/dama/topology.ma b/matita/dama/topology.ma index e0a926d76..f068fcbd5 100644 --- a/matita/dama/topology.ma +++ b/matita/dama/topology.ma @@ -16,7 +16,7 @@ set "baseuri" "cic:/matita/topology/". include "sets.ma". -record is_topology X (A: set X) (O: set (set X)) : Prop ≝ +record is_topology (X) (A: set X) (O: set (set X)) : Prop ≝ { top_subset: ∀B. B ∈ O → B ⊆ A; top_empty: ∅︀ ∈ O; top_full: A ∈ O;