generation-number Function

Summary

Returns the current generation number for an object.

Package

system

Signature

generation-number object => integer

Arguments

object⇩

A Lisp object.

Values

integer

An integer.

Description

The function generation-number returns the generation number in which the Lisp object object currently is. See the discussion in 11 Memory Management.

If object is an immediate object then generation-number returns -1. Immediates are objects which are not allocated, including fixnums, characters and short floats, and single floats in 64-bit LispWorks.

See also

11.2 Guidance for control of the memory management system