/**
 * Headless progress (progress §8): one plain, unstyled, append-only line per state transition.
 *
 * This is the surface for `json` and `print` mode — benchmark runs and CI, which is to say the runs
 * that actually matter. Per LESSONS, every serious bug in this project was invisible offline and
 * obvious within one live run, and those live runs are exactly the headless ones; a progress feature
 * that only worked when someone was watching a terminal would miss all of them.
 *
 * Three properties, each load-bearing:
 *
 *  - **Plain words, not glyphs** (§8.1). This stream is read in log files and CI output where the
 *    theme, the width, and often the font are all unknown.
 *  - **stderr, never stdout** (§8.2) — a correctness requirement, not a preference. In JSON mode stdout
 *    IS the event protocol; in print mode it is the assistant's answer, which callers parse.
 *    Interleaving progress into either corrupts a contract someone depends on. The stream is injected
 *    here rather than written directly so that fact is testable, and so nothing in this file can reach
 *    stdout by accident.
 *  - **Append-only, never a redraw** (§8.3). The parent's stderr is shared with everything else in the
 *    process, and cursor movement in a stream being appended to from more than one place corrupts all
 *    of it.
 *
 * A per-event mapping rather than a re-projection: a transition is exactly what an append-only log
 * wants to record, and the panel's collapse/alignment machinery has nothing to contribute to a line.
 */
import type { RunEvent } from "../engine/types.ts";
import type { Outline } from "../progress/types.ts";
/** Where a headless line goes. Injected so a test can capture it and so stdout is unreachable from here. */
export type LineWriter = (line: string) => void;
export interface PlainProgress {
    accept(event: RunEvent): void;
}
/**
 * A headless line writer for one run. `outline` supplies the one fact the log does not carry on its
 * own — a loop's declared `maxIterations`, so `iteration 2/10` can say how close the guard is.
 */
export declare function createPlainProgress(outline: Outline, write: LineWriter): PlainProgress;
//# sourceMappingURL=progress-plain.d.ts.map