objectwithout

Objectwithout is a programming utility concept referring to a function that returns a new object derived from an input object with specified keys removed. It is commonly used in contexts that emphasize immutability, where the original object should not be altered.

Semantics and behavior typically include: the operation is pure and side-effect free, the input object remains unchanged, and a new object is produced containing all keys except those requested for removal. Implementations may accept a single key or a list of keys, and some variants support removing multiple keys in one call. Some versions also offer nested or path-based removal, though many remain shallow and only operate on top-level properties.

In practice, objectwithout is often synonymous with the omit function found in various libraries. Example: objectwithout({ a: 1, b: 2, c: 3 }, ['b', 'c']) yields { a: 1 }. Similar results can be achieved in plain code through object iteration or destructuring to exclude certain properties.

Edge cases and considerations include how to handle keys that do not exist, which are typically ignored; behavior for non-object inputs or null values varies by language and library. Performance is generally linear in the number of properties of the input object, since each property may need to be checked against the list of keys to omit.

Related concepts include pick (creating a new object with a subset of keys), as well as broader immutability helpers, dictionary or map utilities, and data shaping patterns used in API responses and state management.