TS2315

error TS2315: Type ‘CustomRequest‘ is not generic.

Broken Code ❌

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type CustomRequest = {
  url: string;
  data: string;
};

const request: CustomRequest<string> = {
  url: 'https://typescript.tv/',
  data: 'example',
};

Fixed Code ✔️

When supplying a type (recognizable by the use of the diamond operator <>), then we have to make sure that our type actually supports generics to capture the type that we provide:

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type CustomRequest<CustomType> = {
  url: string;
  data: CustomType;
};

const request: CustomRequest<string> = {
  url: 'https://typescript.tv/',
  data: 'example',
};