theorem instCoeFiatSurfaceContinuantFiatBoundary._proof_1
theorem instCoeFiatSurfaceContinuantFiatBoundary._proof_1: ∀ (v : ta3nj1a4.FiatSurface), ta3nj1a4.ContinuantFiatBoundary.Is (Subtype.val v)
theorem instCoeFiatSurfaceContinuantFiatBoundary._proof_1
theorem instCoeFiatSurfaceContinuantFiatBoundary._proof_1: ∀ (v : ta3nj1a4.FiatSurface), ta3nj1a4.ContinuantFiatBoundary.Is (Subtype.val v)