TypeScript Plugged In: Array.length is "unsafe"

https://ducin.dev, #typescript playground: https://tsplay.dev/w1GVXm What every #typescript developer should know is how/when does the compiler track the length of the array. We can learn a lot from lib.es__.d.ts definition files. 00:00 intro 00:25 dive into lib.es__.d.ts 01:08 lib.es5.d.ts - Array.length 01:46 strict length with tuples 02:25 type of array elements 03:04 lib.es5.d.ts - Array elements index signature