Basic questions:
Do we know of any property of a gerund or infinitive which prevents it being treated totally like a type of noun?
Do we know any language which expresses gerunds or infinitives as a noun case?
Background:
I combine noun particles to mark noun properties like declension, plurality, etc.
Examples with accusative particle 'ya,' then with three noun particles:
Na caye ya mwaecolo.
2PS.FUT change ACC everything.
You will change everything.
Na caye yaliaŋc omahál.
2PS.FUT change ACC.DEM1.PL dress.
You will change these dresses.
I have been making verbs into certain non-finite verbs in the same way.
Na hel óya caye.
2PS.FUT avoid GER/INF.ACC change.
You will avoid changing.
For years I have just had it sitting to the side, the only noun particle with nothing else in its category.
It just occurred to me I could treat this infinitive/gerund particle ó as another noun case. As above, it already indicates a type of object for use with some verbs. It can be compatible with other noun particles (e.g., this swimming, many changings, neither swimming nor running...). I could give it some pronouns (like my other cases have) for where the antecedent is an action (e.g., He did so). It would be an unusual case insofar as it can also combine with other cases (It's safe from running.)
Presently I haven't found a sentence where treating gerund-ness as a noun case messes things up. I could use help thinking of a test situation for this.