First Class Citizen

In programming language design, a first-class citizen (also type, object, entity, or value) in a given programming language is an entity which supports all the operations generally available to other entities. These operations typically include being passed as an argument, returned from a function, and assigned to a variable.
Why it matters
First-class citizen as a term derives its meaning by assumption that there are second-class citizens which do not have the freedoms and opportunities of the first-class. This meaning comes from society and its class based discriminatory practices. Use of terms that derive meaning from this history should be avoided.
Instead try saying:
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