proto-typescript

Utility types and implementations based on JavaScript prototypes.
I plan to share the features that are officially available from 2.0.0.

TypedClass

prototype methods

``ts
new TypedArray([1, 2, 3] as const).unshift(4 as const); // TypedArray<[4, 1, 2, 3]>
`

`ts
new TypedArray([1, 2, 3] as const).join(','); // TypedString<'1,2,3'>
`

The return result of 'TypeClass' returns one of the instances of TypeClass again. Therefore, those who know the grammar of JavaScript can use it immediately.

refined methods

`ts
/**
* error case
*/
new TypedArray<'1-3'>([1, 2, 3]).refine([1, 2, 3] as const).join('-');
new TypedArray<'1-3'>([]).refine([1, 2, 3] as const).join('-');
new TypedArray<'1-3'>().refine([1, 2, 3, 4] as const).join('-');
new TypedArray<'1-3'>().refine([0, 1, 2, 3] as const).join('-');

/**
* right case
*/
new TypedArray<'1-3'>().refine([2, 3] as const).join('-');
`

TypedArray, TypedNumber has the refine method, which serves to further narrow down the generic type received as a factor. This helps reduce developer mistakes, but it should be careful because it cannot guarantee actual runtime behavior.

> In the future, improvements will be made at the type level.

toPrimitive method

`ts
new TypedString('abcdef').toPrimitive(); // 'abcdef'
`

You can change it to the primitive type of JavaScript.

`ts
const arr = [...new TypedArray([1, 2, 3, 4, 5] as const)]; // (1 | 2 | 3 | 4 | 5)[]
`

Iterable/Iterator` is supported.