Exploring Tuple Types through Looping over Map Entries

I previously had a .forEach loop set up:

myMap.forEach((val: object, key: number) => {
    console.log(val)
})

Now, I need to include a continue statement which means reworking it into a for loop:

for (let [key, val] of myMap.entries()) => {
    console.log(key) 
    console.log(val) 
    if (something) continue
}

Can someone demonstrate how to define the types for the tuple in the for loop?

This Typescript Playground has been quite useful.

Answer №1

Thanks to TypeScript's clever automatic type inference, the arguments are already correctly typed.

https://i.sstatic.net/15yvj.png

TypeScript has the ability to infer types in most cases without explicit declaration, making it easier for developers.

If you encounter issues when iterating over a Map due to type inconsistencies, consider adjusting the Map's definition instead of manually redefining types during iteration. For example:

const myMap = new Map();

If you later add objects of type number and { amount: number } to the map, use generics to specify the types upfront like this:

const myMap = new Map<number, { amount: number }>();

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