TypeScript Lab: Source Map Error Finder

LAB / EXPLORATION

TypeScript Lab: Source Map Error Finder

Planned

LAB 010 — TypeScript Toolchain
Trace a runtime error back to its TypeScript source.

LAB TypeScript Lab: Source Map Error Finder Preview coming soon

LAB 010

TypeScript Lab: Source Map Error Finder

Concept

Source maps connect generated JavaScript locations to original TypeScript lines.

Concept

Source maps connect generated JavaScript locations to original TypeScript lines.

Objective & Explanation

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

Learning Target

Objective

Trace a runtime error back to its TypeScript source.

Explanation

Source maps connect generated JavaScript locations to original TypeScript lines.

Project Plan

Structure, technologies, data boundary, and source connection.

Structure

project/
├── package.json
├── package-lock.json
├── tsconfig.json
├── index.html
└── src/
    └── app.ts

Technologies

TypeScript
Node.js
npm
HTML
CSS

Data Layer

No persistent data layer. Keep all demonstration values inside the standalone project.

Sandbox Source

package.json, tsconfig.json

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.

function fail(): never {
  throw new Error("Trace this error to app.ts");
}

document.querySelector("#run")!.addEventListener("click", fail);

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: trace a runtime error back to its TypeScript source.

Data: None