devsite/node_modules/yaml/dist/parse/cst-visit.d.ts

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2024-07-08 01:49:38 +00:00
import type { CollectionItem, Document } from './cst.js';
export type VisitPath = readonly ['key' | 'value', number][];
export type Visitor = (item: CollectionItem, path: VisitPath) => number | symbol | Visitor | void;
/**
* Apply a visitor to a CST document or item.
*
* Walks through the tree (depth-first) starting from the root, calling a
* `visitor` function with two arguments when entering each item:
* - `item`: The current item, which included the following members:
* - `start: SourceToken[]` Source tokens before the key or value,
* possibly including its anchor or tag.
* - `key?: Token | null` Set for pair values. May then be `null`, if
* the key before the `:` separator is empty.
* - `sep?: SourceToken[]` Source tokens between the key and the value,
* which should include the `:` map value indicator if `value` is set.
* - `value?: Token` The value of a sequence item, or of a map pair.
* - `path`: The steps from the root to the current node, as an array of
* `['key' | 'value', number]` tuples.
*
* The return value of the visitor may be used to control the traversal:
* - `undefined` (default): Do nothing and continue
* - `visit.SKIP`: Do not visit the children of this token, continue with
* next sibling
* - `visit.BREAK`: Terminate traversal completely
* - `visit.REMOVE`: Remove the current item, then continue with the next one
* - `number`: Set the index of the next step. This is useful especially if
* the index of the current token has changed.
* - `function`: Define the next visitor for this item. After the original
* visitor is called on item entry, next visitors are called after handling
* a non-empty `key` and when exiting the item.
*/
export declare function visit(cst: Document | CollectionItem, visitor: Visitor): void;
export declare namespace visit {
var BREAK: symbol;
var SKIP: symbol;
var REMOVE: symbol;
var itemAtPath: (cst: Document | CollectionItem, path: VisitPath) => CollectionItem | undefined;
var parentCollection: (cst: Document | CollectionItem, path: VisitPath) => import("./cst.js").BlockMap | import("./cst.js").BlockSequence | import("./cst.js").FlowCollection;
}