import { AbortOptions, MaybePromise } from '@mithic/commons';
/** A stack data structure. */
export interface Stack<T> {
    /** Returns the top element of this {@link Stack}, or undefined if empty. */
    back?(options?: AbortOptions): MaybePromise<T | undefined>;
    /** Adds an element to this {@link Stack}. */
    push(item: T, options?: AbortOptions): MaybePromise<unknown>;
    /** Removes and returns the top element of this {@link Stack}, or undefined if empty. */
    pop(options?: AbortOptions): MaybePromise<T | undefined>;
}
/** A {@link Stack} that supports peeking the back (top) element. */
export interface PeekableStack<T> extends Stack<T> {
    back(options?: AbortOptions): MaybePromise<T | undefined>;
}
/** A {@link Stack} with synchronous operations. */
export interface SyncStack<T> extends Stack<T> {
    back?(): T | undefined;
    push(item: T): void;
    pop(): T | undefined;
}
//# sourceMappingURL=stack.d.ts.map