Multiple dynamic property types be ignored

[samchon]

Bug Report

🔎 Search Terms

multiple dynamic property types

🕗 Version & Regression Information

Tried in those versions:

• TS 4.9.5
• TS 5.0.4
• TS 5.10 dev-20230424

⏯ Playground Link

• 1st way: https://www.typescriptlang.org/dev/bug-workbench/?#code/C4TwDgpgBAkgogGwgWwgO2FAvFA3gKCiKgG0AFKASzSgGsIQB7AMygCUIBjRgJwBMAPAEM0IADRQRIAHwBdAPwAuKBQgAPYOj4BnKACJOAC0oI+PdHsLFr82IhTpgJWVetFl8JKgwBufAF8-fG40bUwIL0cPe29MHAJrIxMzdGUSXH8JDNkxVyhtRlRgYzQAc2UM3MDgxlDGJAA6BEZSgAoIhwwASh8gA
• 2nd way: https://www.typescriptlang.org/dev/bug-workbench/?#code/C4TwDgpgBAkgogGwgWwgO2FAvFA3gKCiKgGMALASwQBMAndAfgC5ZEV1gBtAXQG5DinANYQQLAM7BaFNAHNuzVklQZ+AX374SAezSSoEZRxbwjGbHgFFyVOuhadcagDR413Z1ajjtqYJTkWJ08NLV0fJAA6BG1ZAApDdgwASl4gA

💻 Code

1st way

type IElement = {
    [P in keyof Record<any, any>]?: P extends "children"
        ? IElement[]
        : IElement;
};

const element: IElement = {
    children: [{}, {}],
    something: {},
};
console.log(element);

2nd way

type IElement = {
    children?: IElement[];
    [key: string]?: IElement;
};

const element: IElement = {
    children: [{}, {}],
    something: {},
};
console.log(element);

🙁 Actual behavior

I hope that children: IElement[] type works

🙂 Expected behavior

TS compiler can't identify children: IElement[] type, and just enforce to use only [key: string]: IElement type.

I can't sure this is a bug that TS compiler failed to detect multiple dynamic property types, or a spec do not allowing it.

[fatcerberus]

This is not currently possible. You want #17867

[samchon]

@fatcerberus Ah, this is called hybrid type. Thanks for your link.