freelist

Outsource of Node's internal FreeList module (originally by Ryan Dahl)

var fl = require("freelist");

var me = new fl("fralloc", 100, Number);

me.free(Number(100));
me.free(Number(101));

me.alloc(123)
// 100

me.alloc(123)
// 101

me.alloc(123)
// 123