pub fn define_constraints<Args: PartialEq + Clone + Debug + 'static>(
ctx: &mut StepContext<'_>,
args: &Args,
generator: ConstraintGenerator<Args>,
) -> GeopResult<()>Expand description
Defines the constraints generator makes of args in the step being
run, one of the part’s Constraints. Each is checked: its
derivatives are by states its generator read, a row per residual, as
many numbers as a step of the state takes. A plain function, like a
make (Make).
A constraint whose residual reads a target that itself read the state — geometry the state drives, a sketch following a placed part — is refused, naming the constraint, the target and the state: a solve differentiates a constraint by the states it reads, and could not see how such a target moves with them.
A step that fails here leaves a failed target, which fails
Constraints::of: a solve must not go on without a constraint it
could not make.