Enum Checkpoint 

pub enum Checkpoint {
    IterStart,
    AfterBarrierUpdate,
    AfterSearchDirection,
    AfterStep,
    StepRejected,
    PreRestoration,
    PostRestoration,
    Terminated,
}

Where in the main loop a checkpoint fired.

Variants

IterStart

Top of an outer iteration — after the intermediate callback, before this iteration’s Newton step is computed. The iterate, multipliers, and μ all reflect the accepted point from the previous iteration.

AfterBarrierUpdate

After the barrier parameter μ was updated for this iteration (before the search direction is computed).

AfterSearchDirection

After the primal-dual Newton step was computed — the search direction δ (data.delta), the applied regularization, and the KKT factorization are available.

AfterStep

After the line search chose a step length and the trial point was accepted — α (info_alpha_*) and the new iterate are in place.

StepRejected

The line search rejected this iteration’s step — it hit the tiny-step floor or exhausted its backtracks without an acceptable point, and the solver is about to fall into restoration. The search direction δ and the un-accepted current iterate are intact for inspection. The “why did the line search give up here?” stop, distinct from the restoration entry that follows.

PreRestoration

Just before the algorithm switches into the restoration phase — the iterate that tripped restoration is intact. The most-requested “why did this go to restoration?” stop.

PostRestoration

Just after the restoration phase returns, so its effect on the iterate can be inspected.

Terminated

The solve has finished (or is about to): fired once before optimize returns, at the final iterate, carrying the outcome via DebugCtx::status. Lets a debugger drop in for a post-mortem at the failing (or final) point. The DebugAction returned at this checkpoint is ignored — the solve is already over, so there is nothing left to resume or stop.

Implementations

impl Checkpoint

pub fn as_str(self) -> &'static str

The stable wire/CLI protocol name for this checkpoint. These strings are intentionally not the variant identifiers (AfterBarrierUpdate → "after_mu", PreRestoration → "pre_restoration_entry") — they’re the names the JSON protocol and stop-at use, so match on the variant, not the string. Locked by the checkpoint_as_str_is_stable test.

pub fn is_sub_iteration(self) -> bool

Sub-iteration checkpoints (everything between IterStart and the next IterStart).

Trait Implementations

impl Clone for Checkpoint

fn clone(&self) -> Checkpoint

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Checkpoint

impl Debug for Checkpoint

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Checkpoint

impl PartialEq for Checkpoint

fn eq(&self, other: &Checkpoint) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl StructuralPartialEq for Checkpoint