deep-omit

DeepOmit<Type, Filter> constructs a type by picking all properties from type Type and removing properties which values are never or true in type Filter

interface EnglishClass {
  students: { name: string; score: number }[];
  teacher: {
    name: string;
    yearsOfExperience: number;
  };
  year: number;
}

type AnonymousEnglishClass = DeepOmit<
  // ^? { students: { score: number }[]; teacher: { yearsOfExperience: number }; year: number }
  EnglishClass,
  {
    students: { name: never }[];
    teacher: {
      name: never;
    };
  }
>;

It doesn't validate that all Filter properties exist in type Type:

type UnknownEnglishClass = DeepOmit<
  EnglishClass,
  {
    id: never;
    students: { id: never }[];
    teacher: {
      id: never;
    };
  }
>;

If you'd like type a second type parameter Filter to be validated against a structure of a first type parameter Type, please use StrictDeepOmit<Type, Filter>.

Useful in functions which cannot access specified properties

declare const englishClass: EnglishClass;

const takeSurvey = (englishClass: AnonymousEnglishClass) => {
  // Property 'name' does not exist on type '{ yearsOfExperience: number; }'
  englishClass.teacher.name;
  //                   ^^^^
  // Property 'name' does not exist on type '{ score: number; }'
  englishClass.students[0].name;
  //                       ^^^^
};

takeSurvey(englishClass);

⚠️ Limitations:

• DeepOmit cannot be used when Type is generic type – #343
• DeepOmit only limits access to specified properties in your codebase, but doesn't remove them in runtime

TS Playground – https://tsplay.dev/wedDdW