This is what the Church actually teaches (a provision from Canon Law of the Latin Rite, from the 20th century is not "Church teaching"):
From the Catechism of Trent,
Pars I
Caput X
Quaestio VIII
"Those Who Are Not Members Of The Church"
Hence there are but three classes of persons excluded from the Church's pale: infidels, heretics and schismatics, and excommunicated persons.
Infidels are outside the Church because they never belonged to, and never knew the Church, and were never made partakers of any of her Sacraments.
Heretics and schismatics are excluded from the Church, because they have separated from her and belong to her only as deserters belong to the army from which they have deserted.
It is not, however, to be denied that they are still subject to the jurisdiction of the Church, inasmuch as they may be called before her tribunals, punished and anathematised.
Finally, excommunicated persons are not members of the Church, because they have been cut off by her sentence from the number of her children and belong not to her communion until they repent.
But with regard to the rest, however wicked and evil they may be, it is certain that they still belong to the Church: Of this the faithful are frequently to be reminded, in order to be convinced that, were even the lives of her ministers debased by crime, they are still within the Church, and therefore lose nothing of their power.
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So, it's either there are "various degrees of excoms", and can be understood as a penalty other than a status, or you have to say all excommunicati are non members and cut off from the Church (Body).