Function check_shape_on_value 

pub fn check_shape_on_value(
    shape: &dyn Shape,
    cx: &mut Cx,
    value: Value,
) -> Result<ShapeMatch>

Check a runtime value against a shape, returning the resulting match.

A thin entry point that defers to the shape’s own check_value; it exists so callers can drive a shape without depending on the Shape trait directly.