async-traverse-tree
v1.1.0
Published
Asynchronously iterates and transforms tree-like structures.
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async-traverse-tree
async-traverse-tree
is a lightweight, asynchronous library for traversing and mapping tree-like data structures.
Features
- Asynchronously traverses and modifies objects and arrays.
- Easy-to-use API for applying custom functions to each value in the tree.
- Prevents circular references to maintain data integrity.
Installation
You can install async-traverse-tree
using npm or yarn:
npm install async-traverse-tree
or
yarn add async-traverse-tree
Usage
Here's a simple example of how to use async-traverse-tree
with the updated implementation:
// Import the 'traverse' function from 'async-traverse-tree'
import { traverse } from 'async-traverse-tree';
// Define a custom mapper function
const mapper = async (key, value) => {
// Apply your custom logic here asynchronously
return value;
};
// Your data structure
const data = /* Your data structure here */;
// Asynchronously traverse and map the data
traverse(data, mapper)
.then(result => {
// Process the result
console.log(result);
})
.catch(error => {
console.error(error);
});
Controlling Tree Traversal
The async-traverse-tree module exports two symbols that can be used to control the traversal process:
- STOP: Returning STOP from your mapper function will halt traversal of the current branch. No child nodes will be processed.
- REMOVE: Returning REMOVE from your mapper function will remove the current key/value pair from the tree.
import { traverse, STOP, REMOVE } from 'async-traverse-tree';
const mapper = async (key, value) => {
// stop traversing deeper into this branch
if (skipCondition) {
return STOP
}
// remove this key/value completely
if (removeCondition) {
return REMOVE
}
// Apply your custom logic here asynchronously
return value;
};
Motivation
An easy way to iterate over an object-like structure is to use JSON.parse(JSON.stringify(obj), (key, value) => ... )
.
The problem with this approach is that it can't handle circular references and is synchronous. async-traverse-tree
can act like an async drop-in replacement for that which can also handle circular references.