Type is not assignable to type LibraryManagedAttributes - reactjs

I am trying to create array field component that will accept any React Functional component that has BaseProps. However I get an error when rendering Component in ArrayField.
Please see code below. Any ideas what's wrong here?
type BaseProps<T> = {
name: string;
convertValue?: (value: T) => T;
};
type CompanyType = {
address: string;
employees: number;
};
type CompanyProps = BaseProps<CompanyType> & {
required?: boolean;
};
const Company = (props: CompanyProps) => {
return <div>{/** */}</div>;
};
type ArrayFieldProps<T, V extends React.FC<BaseProps<T>>> = {
Component: V;
componentProps: React.ComponentProps<V>;
values: T[];
};
const ArrayField = <T, V extends React.FC<BaseProps<T>>>({
Component,
values,
componentProps
}: ArrayFieldProps<T, V>) => {
return (
<React.Fragment>
{values.map((_, index) => (
<Component key={index} {...componentProps} />
))}
</React.Fragment>
);
};
export const App = () => {
const companies: CompanyType[] = [];
return (
<ArrayField
values={companies}
Component={Company}
componentProps={{
name: 'company',
convertValue: (value) => ({
...value,
address: value.address.toUpperCase()
}),
required: true
}}
/>
);
};

I would do it slightly differently. Component types are quite complex so IMO it's easier to reason about simpler types, and it this scenario it solves your problem. Instead of using the Component as a "base" for your interface, use props. Like this:
type BaseProps<T> = {
name: string;
convertValue?: (value: T) => T;
};
type ArrayFieldProps<T, P extends BaseProps<T>> = {
Component: React.ComponentType<P>;
componentProps: P;
values: T[];
};
const ArrayField = <T, P extends BaseProps<T>>({
Component,
values,
componentProps
}: ArrayFieldProps<T, P>) => {
return (
<>
{values.map((_, index) => (
<Component key={index} {...componentProps} />
))}
</>
);
};
So as you can see the main difference is that the second generic type has to extend BaseProps<T> instead of a component type with specific props (this is most likely where TypeScript gives up and it results in problems with key prop) and ultimately you want your Component to be any valid React component (whether it's class or a function one). Of course if you really insist on enforcing function components you can change React.ComponentType to React.FC and it would still work.

You have to take into consideration the
key={index}
portion because there is a mismatch from the expected type and what is passed. This portion is not included in any of the types and I guess typescript just interprets it as value to be passed (not actual key).
You may try to move it on outer div just to see if the situation improves.

Related

incompatible function argument in component props

I have a component that takes a list of items, known to have an ID, and a function that filters those items.
The type with an ID is a generic type of item, that all items will have.
But more specific items will include other props.
type GenericItem = {
id: string;
}
type SpecificItem = {
id: string;
someOtherProp: boolean;
}
I also have a function type, that uses the generic type to operate on.
type GenericItemFunction = (item: GenericItem) => boolean;
I then have this component that uses the GenericItem and GenericItemFunction in its props.
type CompProps = {
fn: GenericItemFunction;
items: GenericItem[];
}
const Comp: React.FC<CompProps> = ({ fn, items }) => <></>;
When I try to use this component with the Specific type, I am getting errors saying I cannot use an implementation of GenericItemFunction because the types for item are not compatible.
const App = () => {
const items: SpecificItem[] = [];
const filter = (item: SpecificItem) => item.someOtherProp;
return (
<Comp
fn={filter} // error on `fn` prop
items={items}
/>
)
}
The typescript error I receive is:
Type '(item: SpecificItem) => boolean' is not assignable to type 'GenericItemFunction'.
Types of parameters 'item' and 'item' are incompatible.
Property 'someOtherProp' is missing in type 'GenericItem' but required in type 'SpecificItem'.
I guess I have two questions;
Firstly, Why is there a conflict when both types expect the id: string property?
Secondly, is there a more sane way to do something like this?
My first though was the type for item on the GenericItemFunction could be inferred from the value provided to the items prop in the App component.
But to be completely honest, I'm not sure how that would look...
My other thought was to have the Comp be a generic, but not show to use a react component that uses generics... Seems like jsx/tsx doesn't really support that syntax.
I expect something like this to throw all sorts of errors.
const Comp = <T extends GenericItem,>({ fn, items }) => <></>;
const App = () => {
return <Comp<SpecificType> />;
}
Finally, I did try this and there aren't any errors. But the downside is the type for items is inferred to be any.
type GenericItem = {
id: string;
}
type SpecificItem = {
id: string;
someOtherProp: boolean;
}
type GenericItemFunction <T> = (item: T) => boolean;
type CompProps <T extends GenericItem = any> = {
fn: GenericItemFunction<T>;
items: T[];
}
const Comp: React.FC<CompProps> = ({ fn, items }) => <></>;
const App = () => {
const items: SpecificItem[] = [];
const filter = (item: SpecificItem) => item.someOtherProp;
return (
<Comp
fn={filter}
items={items}
/>
)
}
Here's a link to the playground I've been using.
https://www.typescriptlang.org/play?#code/C4TwDgpgBA4hB2EBOBLAxgSWBAtlAvFAN4BQAkCgCYBcUAzsKvAOYDcJAviSaJFAMqQ0KAGbosuAsRJRZUKrQZM2MuXQD2OCAHlgAC2QAFJOrC0ARuvUAbCAEN47Lj3DQ4iVJmw4AYgFd4NGAUdXgoAB4AFQA+KQAKFG9aSIBKAljLG3tHbhc+AGFNMGNTOgjIqAgAD2x4SjL3ZHFvKQcQWMJSMhF4WkbPCV8AoJD4KOj2OXlvOmSAbQBdJxI0UIYoQpwzKAAleyCAOh988M3ikzA6Dqg4oigegBpp3DKONPxY8OjwgHoJ7lW8HWAEEwGB4u9YqQpoD1okXrRBBBhGIvLhFlJFpM5LDgPcUNZsEh4vCcIihKJmrhIc8cAcNFpdAYkCUwOxVLIkBBgH4kGE4hyphEzoKhXIevgiGJCcguGKxaS6JLFXL5X9BSlOEA
UPDATE:
Why did you use any as default for GenericItem type? Without this I believe it should properly infer Genericitem from GenericItemFunction. – tymzap
Removing the = any for the CompProps typedef causes errors in the Comp declaration...
type CompProps <T extends GenericItem> = {
fn: GenericItemFunction<T>;
items: T[];
}
const Comp: React.FC<CompProps> = ({ fn, items }) => <></>; // this line has the error
Generic type 'CompProps' requires 1 type argument(s).
Meaning, I still have to declare the type somewhere. Meaning I need to know the variation of the GenericItem type before I use the component.
SpecificItem is just a representation of the types that happen to overlap with the GenericItem typedef.
In most cases, the Comp wont know what type will actually be used and any doesn't give any useful information to the author.
I'm hoping for something like...
type CompProps <T extends GenericItem> = {
items: <T extends GenericItem>[];
fn: <infer from T>[];
}
But I'm not sure if this exists, or something like it.
:face_palm:
The CompProps using <T extends GenericType = any> is the correct way to do this.
type CompProps <T extends GenericItem = any> = {
items: T[];
filter: (item: T) => boolean;
}
const Comp: React.FC<CompProps> = (props) => <></>;
The magic is happening here:
const App = () => {
...
const filter = (item: SpecificItem) => item.someOtherProp;
...
}
The const Comp: React.FC<CompProps> doesn't care what the generic type is, hence = any. As long as it has at least the same shape as GenericType.
But inside the App component, where we are defining the method for the filter prop, we are declaring the SpecificItem typedef in the argument. Only that method uses the SpecificItem typedef. CompProps only cares it meets the required shape of GenericItem.
Hope that helps someone.
In most cases, the Comp wont know what type will actually be used and any doesn't give any useful information to the author.
To me, that means Comp is generic. So I would remove the = any on CompProps:
type CompProps<T extends GenericItem> = {
fn: GenericItemFunction<T>;
items: T[];
};
...and then define Comp as generic. There's probably a way to do that with React.FC, but personally I don't use React.FC so I don't know what it is. :-) React.FC doesn't do much of anything for you, and as some people point out, amongst other things it says your component accepts children whether it does or not. I prefer to be explicit about it when my components accept children.
So I'd define Comp like this:
const Comp = <T extends GenericItem>({ fn, items }: CompProps<T>) => {
// Just to show that `fn` and `items` play together:
const example = items.map(fn);
return <>{example}</>;
};
If you wanted it to have children, you can add them easily enough. Use string if you only want to support text, or React.Node if you want to allow just about anything:
// Does allow children:
type Comp2Props<T extends GenericItem> = {
fn: GenericItemFunction<T>;
items: T[];
children: React.ReactNode;
};
const Comp2 = <T extends GenericItem>({ fn, items, children }: Comp2Props<T>) => {
// Just to show that `fn` and `items` play together:
const example = items.map(fn);
return <>{example}</>;
};
Either way, it works well in your scenario:
const App = () => {
const items: SpecificItem[] = [];
const filter = (item: SpecificItem) => item.someOtherProp;
return <>
<Comp
fn={filter}
items={items}
/>
</>;
};
And the types mean it doesn't work in places you probably don't want it to:
const App2 = () => {
const genericItems: GenericItem[] = [];
const filterGeneric = (item: GenericItem) => item.id === "example"; // Silly definition, but...
const specificItems: SpecificItem[] = [];
const filterSpecific = (item: SpecificItem) => item.someOtherProp;
return <>
{/* Desirable error, `fn` can't handle `GenericItem`s, only `SpecificItem`s */}
<Comp
fn={filterSpecific}
items={genericItems}
/>
{/* Works, `fn` handles the supertype of the items, which is fine */}
<Comp
fn={filterGeneric}
items={specificItems}
/>
{/* Desirable error because `Comp` doesn't [now] support `children` */}
<Comp
fn={filterSpecific}
items={specificItems}
>
children here
</Comp>
{/* Works because `Comp2` does support `children`*/}
<Comp2
fn={filterSpecific}
items={specificItems}
>
children here
</Comp2>
</>;
};
Playground link

Enforced properties on a React component with TypeScript

I would like to enforce properties on a React component with TypeScript, but I am getting weird behaviour. Bellow I am pasting only simple examples:
function FunctionalComponent(props: { color: string }) {
return <></>;
}
type ComponentWithName<I extends React.FunctionComponent<{ name: string } & React.ComponentProps<I>>> = I;
const component: ComponentWithName<typeof FunctionalComponent> = FunctionalComponent;
The code above will pass even I declared that the component must have a property name. With this code I need to get an errror, because the FunctionalComponent does not include a name property.
On the other hand, this works:
function FunctionalComponent(props: { color: string }) {
return <></>;
}
type ComponentWithName<I extends React.FunctionComponent<{ name: string }>> = I;
const component: ComponentWithName<typeof FunctionalComponent> = FunctionalComponent
This code will throw a TypeScript error, exactly what I need. But the issue is, that the FunctionalComponent can not have additional properties unless I add them manually to the React.FunctionComponent.
The goal is to enforce a component to have the "name" property, but allow to have more additional (not specified) properties.
I am using TypeScript version 4.4.4 and React version 17.0.2
Edit:
The true use case is this:
function Component<
I extends
| React.ComponentClass<
{
onChange: (event: React.ChangeEvent) => void;
} & React.ComponentProps<I>
>
| React.ComponentType<
{
onChange: (event: React.ChangeEvent) => void;
} & React.ComponentProps<I>
>
>(
props: {
component?: I;
} & Omit<React.ComponentProps<I>, "onChange">
) {
const { component: Component, ...rest } = props;
const handleChange = () => {
//
};
return (
<div>
{Component ? (
<Component
{...(rest as React.ComponentProps<I>)}
onChange={handleChange}
/>
) : (
<input onChange={handleChange} />
)}
</div>
);
}
class ComponentClass extends React.Component<{
color: "blue" | "yellow";
}> {
render() {
return (
<input style={{color: this.props.color}} />
);
}
}
function ComponentFunction(props: { color: "blue" | "yellow" }) {
return <input style={{color: props.color}} />;
}
function App() {
return (
<>
<Component component={ComponentClass} color="blue" />
<Component component={ComponentFunction} color="blue" />
</>
);
}
The <Component component={ComponentClass} color="blue" /> will throw an type error but the <Component component={ComponentFunction} color="blue" /> does not. I need to enforce passed components to have the onChange property with the specified type.
I may be missing something, but do you not just need to enforce the type of the Props rather than create a typed component?
interface NameProps {
name: string;
}
type NamedComponent<T extends NameProps> = (props: T) => JSX.Element;
const notANamedComponent: NamedComponent<{ int: number }> // ...this will give you an error
const aNamedComponent: NamedComponent<{ int: number; name: string}> //OK
The issue is that passing extra fields to the component is always valid, if you want to require it to do something with it is harder to type.
For instance this is valid code:
// from this context the argument will be called with an argument with both a and b properties
function takeF(f: (data: {a:string, b:number})=>any){}
// this function takes an object with an a property, but passing other properties would still be valid
function f(data: {a:string}){}
// this is allowed because passing an object with extra fields is still valid.
takeF(f)
The reason you are getting an error with {name: string} and {color:string} is because those have no overlap so typescript does give you errors, so the solution is to constrain your generic to what you actually need.
declare function Component<
ComponentProps extends { onChange: (event: React.ChangeEvent) => void; }
>(
props: {
component?: React.ComponentClass<ComponentProps> | React.ComponentType<ComponentProps>;
} & Omit<ComponentProps, "onChange">
): any
this way if the component doesn't have an onChange then there is no overlap and you get the error you are expecting and if there are extra properties it is fine because those are already being captured by the generic behaviour. Also note this is basically the same thing that #Marcus is saying, just constrain the generic to what you actually need.

React with Typescript -- Generics while using React.forwardRef

I am trying to create a generic component where a user can pass the a custom OptionType to the component to get type checking all the way through. This component also required a React.forwardRef.
I can get it to work without a forwardRef. Any ideas? Code below:
WithoutForwardRef.tsx
export interface Option<OptionValueType = unknown> {
value: OptionValueType;
label: string;
}
interface WithoutForwardRefProps<OptionType> {
onChange: (option: OptionType) => void;
options: OptionType[];
}
export const WithoutForwardRef = <OptionType extends Option>(
props: WithoutForwardRefProps<OptionType>,
) => {
const { options, onChange } = props;
return (
<div>
{options.map((opt) => {
return (
<div
onClick={() => {
onChange(opt);
}}
>
{opt.label}
</div>
);
})}
</div>
);
};
WithForwardRef.tsx
import { Option } from './WithoutForwardRef';
interface WithForwardRefProps<OptionType> {
onChange: (option: OptionType) => void;
options: OptionType[];
}
export const WithForwardRef = React.forwardRef(
<OptionType extends Option>(
props: WithForwardRefProps<OptionType>,
ref?: React.Ref<HTMLDivElement>,
) => {
const { options, onChange } = props;
return (
<div>
{options.map((opt) => {
return (
<div
onClick={() => {
onChange(opt);
}}
>
{opt.label}
</div>
);
})}
</div>
);
},
);
App.tsx
import { WithoutForwardRef, Option } from './WithoutForwardRef';
import { WithForwardRef } from './WithForwardRef';
interface CustomOption extends Option<number> {
action: (value: number) => void;
}
const App: React.FC = () => {
return (
<div>
<h3>Without Forward Ref</h3>
<h4>Basic</h4>
<WithoutForwardRef
options={[{ value: 'test', label: 'Test' }, { value: 1, label: 'Test Two' }]}
onChange={(option) => {
// Does type inference on the type of value in the options
console.log('BASIC', option);
}}
/>
<h4>Custom</h4>
<WithoutForwardRef<CustomOption>
options={[
{
value: 1,
label: 'Test',
action: (value) => {
console.log('ACTION', value);
},
},
]}
onChange={(option) => {
// Intellisense works here
option.action(option.value);
}}
/>
<h3>With Forward Ref</h3>
<h4>Basic</h4>
<WithForwardRef
options={[{ value: 'test', label: 'Test' }, { value: 1, label: 'Test Two' }]}
onChange={(option) => {
// Does type inference on the type of value in the options
console.log('BASIC', option);
}}
/>
<h4>Custom (WitForwardRef is not generic here)</h4>
<WithForwardRef<CustomOption>
options={[
{
value: 1,
label: 'Test',
action: (value) => {
console.log('ACTION', value);
},
},
]}
onChange={(option) => {
// Intellisense SHOULD works here
option.action(option.value);
}}
/>
</div>
);
};
In the App.tsx, it says the WithForwardRef component is not generic. Is there a way to achieve this?
Example repo: https://github.com/jgodi/generics-with-forward-ref
Thanks!
Creating a generic component as output of React.forwardRef is not directly possible 1 (see bottom). There are some alternatives though - let's simplify your example a bit for illustration:
type Option<O = unknown> = { value: O; label: string; }
type Props<T extends Option<unknown>> = { options: T[] }
const options = [
{ value: 1, label: "la1", flag: true },
{ value: 2, label: "la2", flag: false }
]
Choose variants (1) or (2) for simplicity. (3) will replace forwardRef by usual props. With (4) you globally chance forwardRef type definitions once in the app.
Playground variants 1, 2, 3
Playground variant 4
1. Use type assertion ("cast")
// Given render function (input) for React.forwardRef
const FRefInputComp = <T extends Option>(p: Props<T>, ref: Ref<HTMLDivElement>) =>
<div ref={ref}> {p.options.map(o => <p>{o.label}</p>)} </div>
// Cast the output
const FRefOutputComp1 = React.forwardRef(FRefInputComp) as
<T extends Option>(p: Props<T> & { ref?: Ref<HTMLDivElement> }) => ReactElement
const Usage11 = () => <FRefOutputComp1 options={options} ref={myRef} />
// options has type { value: number; label: string; flag: boolean; }[]
// , so we have made FRefOutputComp generic!
This works, as the return type of forwardRef in principle is a plain function. We just need a generic function type shape. You might add an extra type to make the assertion simpler:
type ForwardRefFn<R> = <P={}>(p: P & React.RefAttributes<R>) => ReactElement |null
// `RefAttributes` is built-in type with ref and key props defined
const Comp12 = React.forwardRef(FRefInputComp) as ForwardRefFn<HTMLDivElement>
const Usage12 = () => <Comp12 options={options} ref={myRef} />
2. Wrap forwarded component
const FRefOutputComp2 = React.forwardRef(FRefInputComp)
// ↳ T is instantiated with base constraint `Option<unknown>` from FRefInputComp
export const Wrapper = <T extends Option>({myRef, ...rest}: Props<T> &
{myRef: React.Ref<HTMLDivElement>}) => <FRefOutputComp2 {...rest} ref={myRef} />
const Usage2 = () => <Wrapper options={options} myRef={myRef} />
3. Omit forwardRef alltogether
Use a custom ref prop instead. This one is my favorite - simplest alternative, a legitimate way in React and doesn't need forwardRef.
const Comp3 = <T extends Option>(props: Props<T> & {myRef: Ref<HTMLDivElement>})
=> <div ref={myRef}> {props.options.map(o => <p>{o.label}</p>)} </div>
const Usage3 = () => <Comp3 options={options} myRef={myRef} />
4. Use global type augmentation
Add following code once in your app, perferrably in a separate module react-augment.d.ts:
import React from "react"
declare module "react" {
function forwardRef<T, P = {}>(
render: (props: P, ref: ForwardedRef<T>) => ReactElement | null
): (props: P & RefAttributes<T>) => ReactElement | null
}
This will augment React module type declarations, overriding forwardRef with a new function overload type signature. Tradeoff: component properties like displayName now need a type assertion.
1 Why does the original case not work?
React.forwardRef has following type:
function forwardRef<T, P = {}>(render: ForwardRefRenderFunction<T, P>):
ForwardRefExoticComponent<PropsWithoutRef<P> & RefAttributes<T>>;
So this function takes a generic component-like render function ForwardRefRenderFunction, and returns the final component with type ForwardRefExoticComponent. These two are just function type declarations with additional properties displayName, defaultProps etc.
Now, there is a TypeScript 3.4 feature called higher order function type inference akin to Higher-Rank Types. It basically allows you to propagate free type parameters (generics from the input function) on to the outer, calling function - React.forwardRef here -, so the resulting function component is still generic.
But this feature can only work with plain function types, as Anders Hejlsberg explains in [1], [2]:
We only make higher order function type inferences when the source and target types are both pure function types, i.e. types with a single call signature and no other members.
Above solutions will make React.forwardRef work with generics again.
I discovered this question from reading this blog post, and I think there is a more straight-forward way of accomplishing this than the current accepted answer has proposed:
First we define an interface to hold the type of the component using something called a call signature in typescript:
interface WithForwardRefType extends React.FC<WithForwardRefProps<Option>> {
<T extends Option>(props: WithForwardRefProps<T>): ReturnType<React.FC<WithForwardRefProps<T>>>
}
Notice how the function signature itself is declared as generic, not the interface - this is the key to making this work. The interface also extends React.FC in order to expose some useful Component properties such as displayName, defaultProps, etc.
Next we just supply that interface as the type of our component, and without having to specify the type of the props, we can pass that component to forwardRef, and the rest is history...
export const WithForwardRef: WithForwardRefType = forwardRef((
props,
ref?: React.Ref<HTMLDivElement>,
) => {
const { options, onChange } = props;
return (
<div ref={ref}>
{options.map((opt) => {
return (
<div
onClick={() => {
onChange(opt);
}}
>
{opt.label}
</div>
);
})}
</div>
);
});
Sandbox link here
References:
https://stackoverflow.com/a/73795451/2089675

Extends type of accepted props

I have a component that's root node can be overridden with the value of passed prop.
interface Props {
propA?: string
as?: React.ElementType
}
const OverridableComponent = (props: Props) => {
const { as: Tag = 'div', ...otherProps } = props
return <Tag {...props} />
}
And another component that will be used as as.
interface SomeComponentProps {
propB: string //<-- mandatory prop
children?: React.ReactNode
}
const SomeComponent = (props: SomeComponentProps) => {
return <div someProp={props.propB}>{props.children}</div>
}
So, the result that I would love to achieve is something like this
<OverridableComponent propA='optionalProp' as={SomeComponent} />
and I'd like OverridableComponent to merge props from SomeComponent.
<OverridableComponent propA='optionalProp' as={SomeComponent}
propB={/*required form SomeComponentProps */'someValue />
To implement this I tried to use generics.
type Props<T extends ElementType> = {
propA?: string
as?: T
} & React.ComponentProps<T>
it works for the case when as prop is passed, but if it's not, every passed prop even from='string' is allowed, because it's allowed on SVG attributes of React.ElementType.
Any idea how to improve this case?
Is it viable for you to pass the required React.ElementType explicitely as Generic type arguments in JSX? Doing that, you do not rely on compiler inference and can narrow the type properly.
Component:
const AppWithComponent = () => (
<OverridableComponent<typeof SomeComponent>
propA="pa"
propB="pb"
// className="ajsf" ; error
// from='string' ; error
as={SomeComponent}
/>
);
Intrinsic Element:
const AppWithIntrinsicElementExplicit = () => (
<OverridableComponent<"div">
propA="pa"
// propB="pb" ; error
className="yehaa"
// from='string' ; error
as="div" // you also can drop this attribute
/>
);
Codesandbox

React Typescript: FunctionComponent with templated props

I have a component with templated props:
const MyComponent = <Value extends any>({ value }: MyComponentProps<Value>) => <div />;
Which I can use without explicitly specifying the type of Value (it is inferred):
<MyComponent value="1" />
<MyComponent value={1} />
I usually write my components this way:
const MyComponent: FunctionComponent<MyComponentProps> = ({ value }) => <div />;
But haven't found a way to template MyComponent and MyComponentProps with this syntax... Does anyone know how to do it? Thanks in advance!
You can extend your ComponentProps like this:
interface MyComponentProps<T> {
value: T
}
const MyComponent: FunctionComponent<MyComponentProps<string>> = ({ value }) => <div />;
Now value is whatever you pass in <>, for example string or any.
If you want value to be any type:
type MyComponentProps = {
value: any
};
or just one of explicit types (a.k.a. union type):
type MyComponentProps = {
value: string | number
};
const MyComponent: FunctionComponent<MyComponentProps> = ({ value }) => <div />;
Based on your comment you just want this:
interface MyComponentProps<V> {
views: V;
initialView: keyof V;
}
type KeyedFunctionComponent<T> = FunctionComponent<MyComponentProps<T>>;
const MyComponent: KeyedFunctionComponent<Views> = (views, initialViews) => <div />;
Then declare your function component using either an interface or "typeof views" as the generic argument. Which is good I think. But, what you really want is this combined with a generator, which will allow you to bind and template correctly:
// Declare some views constant:
const views = { home: "home", index: "index" };
// Declare a type for our bound views component
interface KeyedProps<V> {
initialView?: keyof V;
}
// declare a type for our input function
interface KeyedWithViewsProps<V> extends KeyedProps<V> {
views: V;
}
// This is the binding function itself
function createKeyedComponent<T>(views: T, toWrap: FunctionComponent<KeyedWithViewsProps<T>>): FunctionComponent<KeyedProps<T>> {
return (props: KeyedProps<T>) => toWrap({views, initialView: props.initialView});
}
// Call the binder, and pass in the function we want to bind.
const MyComponent = createKeyedCompnonet(views, () => <div />);
// Now, using the component, only requires the optional initialView param, and it it type-checked to ensure it is a member of views
<MyComponent initialView="home" /> // works
<MyComponent initialView="other" /> // doesn't work
This is what I do
export type MyCompProps<ItemType> = {
item: ItemType;
};
export const MyComp = <ItemType>(props: MyCompProps<ItemType>): React.ReactElement => {
return <Text>item.toString</Text>;
}
Then I can just call
<MyComp item={myItem} />
And it figures it out.

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