Extending a chain api in typescript

[wary crypt]

comment().delete().edit("Hello :)")

comment has the method edit, and it extends a generic function which has the method delete

This causes a typescript error because once delete is used it thinks its on the generic function

[west topaz]

pyroteamfortresstwo#0

Playground Link

Preview:```ts
const generic = function () {
const api = {
_deleted: false,
delete() {
this._deleted = true
return this
},
}
return api
}

const comment = function () {
const api = {
...generic(),
_text: "",
edit(text: string) {
this._text = text
...```

You can choose specific lines to embed by selecting them before copying the link.

[kind jolt]

you need to use a this parameter to specify the type

[pure cradle]

Is there a reason why you are writing it with objects rather than classes? This seems like a perfect use case.

[west topaz]

nonspicyburrito#0

Playground Link

Preview:```ts
class Entity {
deleted = false

public delete() {
this.deleted = true
return this
}
}

class CommentEntity extends Entity {
text = ""

public edit(text: string) {
this.text = text
return this
}
}

new CommentEntity().delete().edit("hello world")
...```

You can choose specific lines to embed by selecting them before copying the link.

[kind jolt]

if you do need to avoid classes for some reason, here's a version that uses a this parameter:

[west topaz]

mkantor#0

Playground Link

Preview:```ts
const generic = function () {
const api = {
_deleted: false,
delete<T extends {_deleted: boolean}>(this: T) {
this._deleted = true
return this
},
}
return api
}

const comment = function () {
const api = {
...generic(),
...```

You can choose specific lines to embed by selecting them before copying the link.