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- /**
- * Some of the internal operations of micromark do lots of editing
- * operations on very large arrays. This runs into problems with two
- * properties of most circa-2020 JavaScript interpreters:
- *
- * - Array-length modifications at the high end of an array (push/pop) are
- * expected to be common and are implemented in (amortized) time
- * proportional to the number of elements added or removed, whereas
- * other operations (shift/unshift and splice) are much less efficient.
- * - Function arguments are passed on the stack, so adding tens of thousands
- * of elements to an array with `arr.push(...newElements)` will frequently
- * cause stack overflows. (see <https://stackoverflow.com/questions/22123769/rangeerror-maximum-call-stack-size-exceeded-why>)
- *
- * SpliceBuffers are an implementation of gap buffers, which are a
- * generalization of the "queue made of two stacks" idea. The splice buffer
- * maintains a cursor, and moving the cursor has cost proportional to the
- * distance the cursor moves, but inserting, deleting, or splicing in
- * new information at the cursor is as efficient as the push/pop operation.
- * This allows for an efficient sequence of splices (or pushes, pops, shifts,
- * or unshifts) as long such edits happen at the same part of the array or
- * generally sweep through the array from the beginning to the end.
- *
- * The interface for splice buffers also supports large numbers of inputs by
- * passing a single array argument rather passing multiple arguments on the
- * function call stack.
- *
- * @template T
- * Item type.
- */
- export class SpliceBuffer<T> {
- /**
- * @param {ReadonlyArray<T> | null | undefined} [initial]
- * Initial items (optional).
- * @returns
- * Splice buffer.
- */
- constructor(initial?: ReadonlyArray<T> | null | undefined);
- /** @type {Array<T>} */
- left: Array<T>;
- /** @type {Array<T>} */
- right: Array<T>;
- /**
- * Array access;
- * does not move the cursor.
- *
- * @param {number} index
- * Index.
- * @return {T}
- * Item.
- */
- get(index: number): T;
- /**
- * The length of the splice buffer, one greater than the largest index in the
- * array.
- */
- get length(): number;
- /**
- * Remove and return `list[0]`;
- * moves the cursor to `0`.
- *
- * @returns {T | undefined}
- * Item, optional.
- */
- shift(): T | undefined;
- /**
- * Slice the buffer to get an array;
- * does not move the cursor.
- *
- * @param {number} start
- * Start.
- * @param {number | null | undefined} [end]
- * End (optional).
- * @returns {Array<T>}
- * Array of items.
- */
- slice(start: number, end?: number | null | undefined): Array<T>;
- /**
- * Mimics the behavior of Array.prototype.splice() except for the change of
- * interface necessary to avoid segfaults when patching in very large arrays.
- *
- * This operation moves cursor is moved to `start` and results in the cursor
- * placed after any inserted items.
- *
- * @param {number} start
- * Start;
- * zero-based index at which to start changing the array;
- * negative numbers count backwards from the end of the array and values
- * that are out-of bounds are clamped to the appropriate end of the array.
- * @param {number | null | undefined} [deleteCount=0]
- * Delete count (default: `0`);
- * maximum number of elements to delete, starting from start.
- * @param {Array<T> | null | undefined} [items=[]]
- * Items to include in place of the deleted items (default: `[]`).
- * @return {Array<T>}
- * Any removed items.
- */
- splice(start: number, deleteCount?: number | null | undefined, items?: Array<T> | null | undefined): Array<T>;
- /**
- * Remove and return the highest-numbered item in the array, so
- * `list[list.length - 1]`;
- * Moves the cursor to `length`.
- *
- * @returns {T | undefined}
- * Item, optional.
- */
- pop(): T | undefined;
- /**
- * Inserts a single item to the high-numbered side of the array;
- * moves the cursor to `length`.
- *
- * @param {T} item
- * Item.
- * @returns {undefined}
- * Nothing.
- */
- push(item: T): undefined;
- /**
- * Inserts many items to the high-numbered side of the array.
- * Moves the cursor to `length`.
- *
- * @param {Array<T>} items
- * Items.
- * @returns {undefined}
- * Nothing.
- */
- pushMany(items: Array<T>): undefined;
- /**
- * Inserts a single item to the low-numbered side of the array;
- * Moves the cursor to `0`.
- *
- * @param {T} item
- * Item.
- * @returns {undefined}
- * Nothing.
- */
- unshift(item: T): undefined;
- /**
- * Inserts many items to the low-numbered side of the array;
- * moves the cursor to `0`.
- *
- * @param {Array<T>} items
- * Items.
- * @returns {undefined}
- * Nothing.
- */
- unshiftMany(items: Array<T>): undefined;
- /**
- * Move the cursor to a specific position in the array. Requires
- * time proportional to the distance moved.
- *
- * If `n < 0`, the cursor will end up at the beginning.
- * If `n > length`, the cursor will end up at the end.
- *
- * @param {number} n
- * Position.
- * @return {undefined}
- * Nothing.
- */
- setCursor(n: number): undefined;
- }
- //# sourceMappingURL=splice-buffer.d.ts.map
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