Intermediate concepts in TypeScript & Web APIs, page 3
WebGL Buffers: Telling the GPU How to Read Your Data
WebGL's vertexAttribPointer is the map you give the GPU to read vertex data from a buffer. It tells your shader how to parse a flat byte array into attributes like position. This is how you link CPU data to the GPU before drawing.
WebGL Uniforms: Global State for Shaders
WebGL uniforms are global constants for your shaders, set once per frame from JavaScript to provide the same value to every vertex and pixel. Use them for scene-wide data like a camera's projection matrix. The footgun: changing a uniform is a CPU-to-GPU call.
MediaRecorder API: Capture Audio and Video in the Browser
The MediaRecorder API is a VCR for your browser, capturing a MediaStream from a camera or screen into a file. Use it for in-browser video recorders or voice memo apps. The footgun: recorded data arrives as Blob objects in an event, not as a direct.
TypeScript's Module Resolution Strategy
TypeScript's moduleResolution is the compiler's search plan for finding files behind import statements. It's crucial when mixing module types (ESM/CJS) or targeting Node.js vs. the browser. The footgun is assuming the default node works for modern ESM.
Modern Bundlers & TypeScript: Transpile, Don't Check
Modern bundlers like Vite prioritize speed by only transpiling TypeScript files, not type-checking them. This enables sub-50ms updates during development. The footgun: your dev server won't report type errors; you must run tsc --noEmit separately.
Module Augmentation: Adding Types to External Libraries
Module augmentation is like monkey-patching for types, letting you add definitions to external modules. Use it to add a user property to Express's Request object.
export = : TypeScript's CommonJS Export Syntax
Think of export = as TypeScript's version of module.exports. It replaces a module's entire export with a single value, like a class or function. It's used for compatibility with CommonJS modules. The footgun is mixing it with standard exports.
Shipping TypeScript Types in package.json
The types field in package.json tells TypeScript where to find your package's type definitions. Use it when publishing a library to enable autocompletion for users. The footgun is putting type dependencies in devDependencies instead of dependencies.
Identifying JS Library Structure for TypeScript Types
To type a JS library, first identify its structure: module, global, or UMD. This dictates your .d.ts file's shape. You'll check docs for import/require or <script> usage. The footgun is misidentifying a UMD library, leading to incorrect import types.
Understanding this in TypeScript
In TypeScript, this is determined by how a function is called, not where it is defined; arrow functions capture the enclosing this lexically, and TypeScript adds optional this parameters to type-check the expected context at compile time.
ES Modules in TypeScript: The Compile-Time Contract
TypeScript ES modules are a compile-time target, not a runtime guarantee. Configure this when targeting modern browsers or Node with native ESM. The footgun is omitting .js extensions in imports, which it requires in ESM output even for .ts source files.
Ambient Module Declarations: Compile-Time Trust Falls
Ambient module declarations are compile-time trust falls: you tell TypeScript the shape of code it cannot see. Use them for untyped npm packages, CSS imports, or CDN scripts.
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