English
There is a canonical ring homomorphism from the stalk of the smooth ring sheaf to R, given by evaluating germs at the base point.
Русский
Существует канонический кольцевой гомоморфизм от stalk гладкого пучка колец к R, заданный оценкой жёрма в базовой точке.
LaTeX
$$$$ \\mathrm{evalHom}(x) : (\\text{stalk at } x) \\to R $$ is a ring homomorphism defined by evaluation at x.$$
Lean4
/-- Canonical ring homomorphism from the stalk of `smoothSheafCommRing IM I M R` at `x` to `R`,
given by evaluating sections at `x`. -/
def eval (x : M) : (smoothSheafCommRing IM I M R).presheaf.stalk x →+* R :=
(smoothSheafCommRing.evalHom IM I M R x).hom