/**
 * Human-friendly duration parsing and formatting.
 *
 * Accepts strings like `"5m"`, `"30s"`, `"1500ms"`, `"2h"`, `"1d"`.
 * A unit suffix is always required.  Always returns **non-negative milliseconds**.
 */
/** A duration value — a string with a unit suffix like `"5m"`, `"30s"`, `"500ms"`. */
export type Duration = string;
/**
 * Node's timer delay is a 32-bit signed integer of milliseconds. A larger
 * `setTimeout`/`child_process` `timeout` overflows and is silently coerced to
 * ~1ms (with a `TimeoutOverflowWarning`), firing almost immediately — the
 * opposite of the caller's intent. Callers that feed a duration into a timer
 * should reject anything above this.
 */
export declare const MAX_TIMER_DELAY_MS = 2147483647;
/**
 * Parse a duration string into milliseconds.
 *
 * @param input - A string like `"5m"`, `"30s"`, `"500ms"`.
 * @returns The duration in milliseconds (always finite and non-negative).
 * @throws If `input` is missing a unit suffix, has an unknown unit, or overflows.
 */
export declare function parseDuration(input: Duration): number;
/**
 * Check whether a value is a valid Duration string (parseable, finite, and
 * non-negative). Note this accepts zero (e.g. `"0s"`); use
 * {@link parsePositiveDuration} when zero should be rejected.
 */
export declare function isValidDuration(input: unknown): input is Duration;
/**
 * Outcome of {@link parsePositiveDuration}: either the parsed milliseconds, or
 * a reason the value was rejected — `"invalid"` (not a duration string with a
 * unit suffix) or `"non-positive"` (parses but is `<= 0`, which would disable a
 * timeout cap).
 */
export type PositiveDurationResult = {
    ok: true;
    ms: number;
} | {
    ok: false;
    reason: "invalid" | "non-positive";
};
/**
 * Parse a duration that must be strictly positive in a single pass, classifying
 * the failure so callers can surface distinct messages without re-parsing. Use
 * this instead of chaining {@link isValidDuration} and a positivity check when
 * you also need the parsed milliseconds.
 */
export declare function parsePositiveDuration(input: unknown): PositiveDurationResult;
/**
 * Outcome of {@link parseTimerDuration}: the parsed milliseconds, or a reason
 * it can't be fed to a timer — `"invalid"` (not a unit-suffixed duration),
 * `"non-positive"` (`<= 0`, which would disable a timeout cap), or `"overflow"`
 * (above {@link MAX_TIMER_DELAY_MS}, which a timer coerces to ~1ms).
 */
export type TimerDurationResult = {
    ok: true;
    ms: number;
} | {
    ok: false;
    reason: "invalid" | "non-positive" | "overflow";
};
/**
 * Parse a duration destined for a `setTimeout`/`child_process` timeout: it must
 * be a positive, unit-suffixed duration within Node's timer range. Classifies
 * the failure so callers can surface distinct messages without re-parsing. This
 * is the timer-safe superset of {@link parsePositiveDuration}; prefer it
 * wherever the value ends up bounding a real timer.
 */
export declare function parseTimerDuration(input: unknown): TimerDurationResult;
/**
 * Format milliseconds as a compact human-readable string.
 * Examples: `formatDuration(300_000)` → `"5m"`, `formatDuration(1500)` → `"1.5s"`.
 */
export declare function formatDuration(ms: number): string;
//# sourceMappingURL=duration.d.ts.map