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namespace;
include rt;
// shared cons cells, a shared string, and a cycle. the collector reclaims
// them once nothing points at them. free of a shared cell does nothing.
// the shared cells again without printing, moved by a few blocks. returns the blocks left over
fn churn(base) {
let a = rt.cons(1, 2), b = rt.cons(a, 3), c = rt.cons(a, 4), cyc = rt.cons(0, 1), tri = rt.triple(5, 6, 7);
cyc[0] = cyc;
a = 0; b = 0; c = 0; cyc = 0; tri = 0;
rt.scrub();
rt.gc();
return rt.live_objects() - base;
}
fn main() {
let base = rt.live_objects(), a, b, c, s, p, q, cyc, n, tri, k, pad;
a = rt.cons(1, 2);
b = rt.cons(a, 3);
c = rt.cons(a, 4);
rt.put_n(rt.car(a)); rt.put_c(32);
rt.put_n(rt.cdr(a)); rt.put_c(32);
rt.put_n(rt.car(rt.car(b))); rt.put_c(32);
rt.put_n(rt.cdr(c)); rt.put_c(32);
rt.put_n(rt.car(b) == a); rt.put_c(32);
rt.put_n(rt.is_shared(a)); rt.put_c(32);
n = rt.live_objects();
rt.free(a);
rt.put_n(rt.live_objects() == n); rt.put_c(32);
rt.put_n(rt.car(a)); rt.put_c(32);
s = rt.n_to_s(42);
p = rt.cons(s, 0);
q = rt.cons(s, 1);
rt.put_n(rt.s_to_n(rt.car(p))); rt.put_c(32);
rt.put_n(rt.car(p) == rt.car(q)); rt.put_c(32);
cyc = rt.cons(0, 1);
cyc[0] = cyc;
rt.put_n(rt.cdr(cyc)); rt.put_c(32);
rt.put_n(rt.car(cyc) == cyc); rt.put_c(32);
tri = rt.triple(5, 6, 7);
rt.put_n(rt.tget(tri, 1)); rt.put_c(32);
a = 0; b = 0; c = 0; s = 0; p = 0; q = 0; cyc = 0; tri = 0;
rt.scrub();
rt.gc();
// the collector marks conservatively: on a small map a word in the code can equal a block's address by
// chance and keep it. shifting where the blocks land must therefore reach a clean count
n = rt.live_objects() - base;
k = 0;
while (n && k < 40) { pad = rt.cons(k, k); rt.scrub(); rt.gc(); n = churn(rt.live_objects()); k++; }
rt.put_n(n); rt.put_c(10);
return 0;
}
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