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generative-token?
make-generative-token
7.3

5 Generative Tokens

 (require rebellion/generative-token) package: rebellion

A generative token is a primitive data type for unique objects. Two generative tokens are only equal? if they are eq?, and the constructor make-generative-token always creates a new token that is not eq? to any other token. Tokens contain no other data — their only use is as a building block for creating other, more complex generative data types.

procedure

(generative-token? v)  boolean?

  v : any/c
A predicate for generative tokens.

Constructs a new generative token that is distinct from all other tokens. Multiple calls to make-generative-token always yield multiple distinct tokens.

Examples:
> (define tok (make-generative-token))
> tok

#<generative-token>

> (equal? tok tok)

#t

> (equal? tok (make-generative-token))

#f