I want to write a type that is generated automatically depending on user data

type CleanPropType = typeof Array | typeof Object | typeof Function | typeof Boolean | typeof String;

type Prop = {
    type: CleanPropType,
    default?:any
}

// define the type of properties for all components

type Props = {
    [name:string]:Prop
}

// define properties for a specific component

let customComponentProps = {
    name:{
        type:String
    }
}

type customComponentGenerator<T extends Props> = {
    [name in keyof T]: ReturnType<T[name].type> // here error. WHY ?
}

// define the type of properties for a specific component
// but here an error occurs when accessing the "type" field 

type customComponent = Partial<customComponentGenerator<typeof customComponentProps>>;

// I need the resulting type to work correctly
let userComponentProps : customComponent = {
    name:'ComponentNameString',
} // ok

let userComponentProps2 : custromComponent = {
    name:false, // must be err
    otherField: 'str' // // must be err
} 

the main problem is that I cannot access the nested field 'type', though T extends Props. thx

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