T
TanStack•11mo ago
correct-apricot

Link `to` prefix helper and typescript

My application supports a single to have access to multiple teams. Almost all links in the application will be links to the same /team/$slug prefix. I am trying to build a Link helper but I am struggling in navigating the types to play nice with my component. Any direction would be appreciated. Example component: 
import { Link, LinkComponentProps } from "@tanstack/react-router";
import { useTeam } from "~/hooks/use-team";

export const TeamLink: React.FC<
  LinkComponentProps<"a"> & {
    params: Record<string, unknown>;
  }
> = ({ to, params, ...props }) => {
  const { team } = useTeam();
  return (
    <Link
      to={`/team/$teamSlug${to}`}
      params={{ ...params, teamSlug: team.slug }}
      {...props}
    >
      {props.children}
    </Link>
  );
};
import { Link, LinkComponentProps } from "@tanstack/react-router";
import { useTeam } from "~/hooks/use-team";

export const TeamLink: React.FC<
  LinkComponentProps<"a"> & {
    params: Record<string, unknown>;
  }
> = ({ to, params, ...props }) => {
  const { team } = useTeam();
  return (
    <Link
      to={`/team/$teamSlug${to}`}
      params={{ ...params, teamSlug: team.slug }}
      {...props}
    >
      {props.children}
    </Link>
  );
};
5 Replies
foreign-sapphire
foreign-sapphire•11mo ago
did you check https://tanstack.com/router/latest/docs/framework/react/guide/custom-link ?
Custom Link | TanStack Router React Docs
While repeating yourself can be acceptable in many situations, you might find that you do it too often. At times, you may want to create cross-cutting components with additional behavior or styles. Yo...
foreign-sapphire
foreign-sapphire•11mo ago
btw looks like you need a relative link
correct-apricot
correct-apricotOP•11mo ago
Thanks for the quick response. I did check the docs. Those work great for adding props to the resulting element, but do not help much in constructing a to value thats typed appropriately. But you know what, as alwasy when you ask a question the answer may come to you. GIve me a few min and get back. Im 1000% sure there is a better way but in case anyone else stubles across this, its how I unblocked myself. 
import { Link, LinkComponentProps } from "@tanstack/react-router";
import { useTeam } from "~/hooks/use-team";

type LinkTo = LinkComponentProps<"a">["to"];
type WithoutTeamPrefix<T> = T extends `/team/$teamSlug${infer Rest}`
  ? Rest
  : never;
type NewUnionType = WithoutTeamPrefix<LinkTo>;

type LinkParams = LinkComponentProps<"a">["params"];
type WithoutTeamSlugParams<T> = T extends { teamSlug?: string | undefined }
  ? Omit<T, "teamSlug">
  : T; // Fallback to T if it doesn't match

type NewLinkParams = LinkParams extends infer U
  ? U extends any
    ? WithoutTeamSlugParams<U>
    : never
  : never;

export type TeamLinkProps = Omit<LinkComponentProps<"a">, "to" | "params"> & {
  to: NewUnionType;
  params: NewLinkParams;
};

export const TeamLink: React.FC<TeamLinkProps> = ({ to, params, ...props }) => {
  const { team } = useTeam();
  return (
    <Link
      to={`/team/$teamSlug${to}` as LinkTo}
      params={{ ...(params as object), teamSlug: team.slug }}
      {...props}
    >
      {props.children}
    </Link>
  );
};
import { Link, LinkComponentProps } from "@tanstack/react-router";
import { useTeam } from "~/hooks/use-team";

type LinkTo = LinkComponentProps<"a">["to"];
type WithoutTeamPrefix<T> = T extends `/team/$teamSlug${infer Rest}`
  ? Rest
  : never;
type NewUnionType = WithoutTeamPrefix<LinkTo>;

type LinkParams = LinkComponentProps<"a">["params"];
type WithoutTeamSlugParams<T> = T extends { teamSlug?: string | undefined }
  ? Omit<T, "teamSlug">
  : T; // Fallback to T if it doesn't match

type NewLinkParams = LinkParams extends infer U
  ? U extends any
    ? WithoutTeamSlugParams<U>
    : never
  : never;

export type TeamLinkProps = Omit<LinkComponentProps<"a">, "to" | "params"> & {
  to: NewUnionType;
  params: NewLinkParams;
};

export const TeamLink: React.FC<TeamLinkProps> = ({ to, params, ...props }) => {
  const { team } = useTeam();
  return (
    <Link
      to={`/team/$teamSlug${to}` as LinkTo}
      params={{ ...(params as object), teamSlug: team.slug }}
      {...props}
    >
      {props.children}
    </Link>
  );
};
foreign-sapphire
foreign-sapphire•11mo ago
how about 
import {
  AnyRouter,
  Constrain,
  InferMaskFrom,
  InferMaskTo,
  InferTo,
  Link,
  LinkComponentProps,
  RegisteredRouter,
} from '@tanstack/react-router';

function useTeam() {
  return { team: { slug: 'slug' } };
}

export type ValidateLinkOptions<
  TOptions,
  TComp = 'a',
  TRouter extends AnyRouter = RegisteredRouter
> = Constrain<
  TOptions,
  LinkComponentProps<
    TComp,
    TRouter,
    '/team/$teamSlug',
    InferTo<TOptions>,
    InferMaskFrom<TOptions>,
    InferMaskTo<TOptions>
  >
>;

export function TeamLink<TOptions>(
  props: ValidateLinkOptions<TOptions> & { children: React.ReactNode }
) {
  const { team } = useTeam();

  return (
    <Link
      from="/team/$teamSlug"
      {...props}
      params={{ teamSlug: team.slug, ...props }}
    >
      {props.children}
    </Link>
  );
}

function Foo() {
  return (
     <TeamLink to="./$some/xyz" params={{ some: 'foo' }}>
      hello team
    </TeamLink>
  );
}
import {
  AnyRouter,
  Constrain,
  InferMaskFrom,
  InferMaskTo,
  InferTo,
  Link,
  LinkComponentProps,
  RegisteredRouter,
} from '@tanstack/react-router';

function useTeam() {
  return { team: { slug: 'slug' } };
}

export type ValidateLinkOptions<
  TOptions,
  TComp = 'a',
  TRouter extends AnyRouter = RegisteredRouter
> = Constrain<
  TOptions,
  LinkComponentProps<
    TComp,
    TRouter,
    '/team/$teamSlug',
    InferTo<TOptions>,
    InferMaskFrom<TOptions>,
    InferMaskTo<TOptions>
  >
>;

export function TeamLink<TOptions>(
  props: ValidateLinkOptions<TOptions> & { children: React.ReactNode }
) {
  const { team } = useTeam();

  return (
    <Link
      from="/team/$teamSlug"
      {...props}
      params={{ teamSlug: team.slug, ...props }}
    >
      {props.children}
    </Link>
  );
}

function Foo() {
  return (
     <TeamLink to="./$some/xyz" params={{ some: 'foo' }}>
      hello team
    </TeamLink>
  );
}
@Chris Horobin can we allow to specify e.g. TFrom for ValidateLinkOptions ? I just duplicated the type, but I hope there is a solution with even less code
afraid-scarlet
afraid-scarlet•11mo ago
You can. You just need an intersection. ValidateLinkOptions<TOptions & { from: TFrom }>

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