Deno - JavaScriptの新たな道筋
JSConf JP 2019
@ ThoughtWorks
Deno is a new command-line runtime for executing JavaScript, TypeScript, WebAssembly
Built with
V8
TypeScript
Rust
Why?
Node.js was designed in 2009
Promises, Iterators and async/await
ES Modules
Typed Arrays
TypeScript
Problems
design module system with centralised destribution
legacy APIs
security
Deno is a single executable file
always be destributed
compact and independent libraries
Secure executionn by default
access disk,network,.. user must add commandline-flags
Web platform compatibility
Where possible, Deno uses web platform APIs
We have these things called URLs
simple and browser compatible module resolution
No notion of node_modules or index.js. No mmagic resolution
does not require any centralized server
TypeScript build in
use V8 Snapshots to startup TypeScript quickly
mix and migrate from JavaScript > TypeScript > Rust or WebAssembly
A full set of development tools built in
info, install, bundle, ...
The future
Deno 1.0 soon
public compiler API
investigating V8 bytecode cachinng
Speedup TypeScript commpiler
Sinngle Binary bundles
improve workers
Better TypeScript types
...