TypeScript Lab: Parent and Child Node Tree

LAB / EXPLORATION

TypeScript Lab: Parent and Child Node Tree

Planned

LAB 025 — Data Relationships
Render content nodes as a two-level hierarchy.

LAB TypeScript Lab: Parent and Child Node Tree Preview coming soon

LAB 025

TypeScript Lab: Parent and Child Node Tree

Concept

parentId turns flat rows into parent-child document structure.

Concept

parentId turns flat rows into parent-child document structure.

Objective & Explanation

What the project should make visible and why the concept matters.

Learning Target

Objective

Render content nodes as a two-level hierarchy.

Explanation

parentId turns flat rows into parent-child document structure.

Project Plan

Structure, technologies, data boundary, and source connection.

Structure

project/
├── package.json
├── tsconfig.json
├── index.html
├── styles.css
└── src/
    └── app.ts

Technologies

TypeScript
HTML
CSS
JSON

Data Layer

Use a small local object, array, or JSON fixture so the transformation stays visible.

Sandbox Source

src/datastore/types.ts

Build Instructions

Build only the focused behavior, then use the visual layer to inspect it.

Setup

Create the standalone project folder and listed files.

Implement

Implement the smallest version that demonstrates the concept.

Run & Inspect

Change one input and observe the visible output change.

Code & Configuration

Starter configuration plus the focused implementation example.

Focused TypeScript

Implement this behavior first, then alter the input.

type Node = { id: string; parentId?: string };

const nodes: Node[] = [
  { id: "purpose" },
  { id: "goals", parentId: "purpose" },
];

const children = nodes.filter(node => node.parentId === "purpose");

Starter Configuration

Keep the project independently buildable.

package.json

{
  "type": "module",
  "scripts": { "build": "tsc" },
  "devDependencies": { "typescript": "^7.0.2" }
}

tsconfig.json

{
  "compilerOptions": {
    "rootDir": "./src",
    "outDir": "./dist",
    "target": "ES2022",
    "module": "ES2022",
    "lib": ["ES2022", "DOM"],
    "strict": true,
    "sourceMap": true
  },
  "include": ["src/**/*.ts"]
}

Expected Visual Result

The output is the proof that the concept is working.

Visible Proof

The browser should visibly demonstrate: render content nodes as a two-level hierarchy.

Data: JSON