a tuple { selector, private key, public key } is created

A record can be viewed as the computer analog of a mathematical tuple, although a tuple may or may not be considered a record, and vice versa, depending on conventions and the specific programming language.

Most typed functional programming languages implement tuples directly as product types

the tuple() function you need can be succinctly written as: export type Lit = string | number | boolean | undefined | null | void | {}; export const tuple = <T extends Lit[]>(...args: T) => args;

const list = ['a', 'b', 'c'] as const; // TS3.4 syntax type NeededUnionType = typeof list[number]; // 'a'|'b'|'c';

possible to tell the compiler to infer the type of a tuple of literals as a tuple of literals, instead of as, say, string[], by using the as const syntax.

Or, maybe better, interpret the list as a tuple type: const list: ['a','b','c'] = ['a','b','c']; // tuple