lean4-htt/src/tests/util/lazy_list.cpp
2014-09-12 16:12:23 -07:00

208 lines
6.5 KiB
C++

/*
Copyright (c) 2013 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Author: Leonardo de Moura
*/
#include <iostream>
#include <utility>
#include "util/interrupt.h"
#include "util/test.h"
#include "util/optional.h"
#include "util/numerics/mpz.h"
#include "util/pair.h"
#include "util/lazy_list.h"
#include "util/lazy_list_fn.h"
#include "util/list.h"
using namespace lean;
lazy_list<int> seq(int s) {
return mk_lazy_list<int>([=]() { return some(mk_pair(s, seq(s + 1))); });
}
lazy_list<int> from(int begin, int step, int end) {
if (begin > end)
return lazy_list<int>();
else
return mk_lazy_list<int>([=]() { return some(mk_pair(begin, from(begin + step, step, end))); });
}
lazy_list<mpz> fact_list_core(mpz i, mpz n) {
return mk_lazy_list<mpz>([=]() { return some(mk_pair(n, fact_list_core(i+1, n*(i+1)))); });
}
lazy_list<mpz> fact_list() {
return fact_list_core(mpz(1), mpz(1));
}
lazy_list<int> mk_simple1(int y) {
int x = 3;
return map(map(append(from(10, 1, 15), from(20, 2, 25)), [=](int v) { return x + v; }),
[=](int v) { return v - y; });
}
lazy_list<int> mk_simple2() {
int x = 10;
return filter(map(interleave(from(0, 2, 10), from(10, 3, 20)), [=](int v) { return x * v; }),
[](int v) { return v > 40; });
}
lazy_list<int> mk_simple3() {
return map_append(from(0, 2, 100), [=](int v) { return from(1, 1, v); });
}
lazy_list<int> loop() {
return mk_lazy_list<int>([=]() {
while (true) {
check_interrupted();
}
return some(mk_pair(0, lazy_list<int>()));
});
}
template<typename T>
void display(lazy_list<T> const & l) {
int buffer[20000];
int i = 0;
for_each(l, [&](T const & v) {
std::cout << v << " ";
buffer[i] = i;
i++;
});
std::cout << "\n";
}
static void tst1() {
lazy_list<int> l = mk_lazy_list<int>([]() { return some(mk_pair(10, lazy_list<int>())); });
lazy_list<int> empty;
lean_assert(l.pull()->first == 10);
lean_assert(!empty.pull());
lean_assert(!l.pull()->second.pull());
list<int> l2{1, 2, 3};
int i = 1;
for_each(to_lazy(l2), [&](int c) {
std::cout << "c: " << c << ", i: " << i << "\n";
lean_assert(c == i);
i++;
});
display(mk_simple1(4));
display(mk_simple2());
display(take(10, fact_list()));
display(take(20, mk_simple3()));
display(orelse(take(10, seq(1)), take(10, seq(100))));
display(orelse(take(10, seq(1)), lazy_list<int>()));
display(orelse(lazy_list<int>(), take(10, seq(100))));
display(orelse(take(0, seq(1)), take(10, seq(100))));
display(orelse(filter(take(100, seq(1)), [](int i) { return i < 0; }), take(10, seq(1000))));
#if defined(LEAN_MULTI_THREAD)
display(timeout(append(append(take(10, seq(1)), loop()), seq(100)), 5));
display(take(10, par(seq(1), loop())));
#endif
}
void tst2() {
lazy_list<int> l(10);
lean_assert(l.pull()->first == 10);
lean_assert(!l.pull()->second.pull());
display(l);
lazy_list<int> l2(20, l);
int i = 0;
for_each(l2, [&](int v) {
lean_assert(i != 0 || v == 20);
lean_assert(i != 1 || v == 10);
i++;
});
lean_assert(i == 2);
}
static void check(lazy_list<int> const & l, list<int> expected) {
display(l);
for_each(l, [&](int v) {
lean_assert(expected);
lean_assert(v == head(expected));
expected = tail(expected);
});
lean_assert(!expected);
}
static void tst3() {
check(repeat(1, [](int v) { if (v > 5) return lazy_list<int>(); else return lazy_list<int>(v+1); }),
list<int>(6));
// The following repeat produces the following "execution trace".
// We use >> << to mark the element being processed
// { >>1<< } 1 produces {2, 4}
// { >>2<<, 4 } 2 produces {3, 6}
// { >>3<<, 6, 4 } 3 produces {4, 8}
// { >>4<<, 8, 6, 4 } 4 produces {5, 10}
// { >>5<<, 10, 8, 6, 4 } 5 produces {6, 12}
// { 6, 12, 10, 8, 6, >>4<< } skips 6, 12, 10, 8, 6 since they are bigger than 5, and 4 produces {5, 10}
// { 6, 12, 10, 8, 6, >>5<<, 10 } 5 produces {6, 12}
// { 6, 12, 10, 8, 6, 6, 12, 10 } skips 6, 12, 10 since they are bigger than 5
check(repeat(1, [](int v) { if (v > 5) return lazy_list<int>(); else return from(v+1, v+1, 2*(v + 1)); }),
list<int>({6, 12, 10, 8, 6, 6, 12, 10}));
}
static void tst4() {
// We use v:k to denote value v was produced with the given k.
// When k == 0, the element is not processed.
// Here is the execution trace for the following repeat_at_most
// { 1:4 }
// { 1:3, 2:3 }
// { 1:2, 2:2, 2:3 }
// { 1:1, 2:1, 2:2, 2:3 }
// { 1:0, 2:0, 2:1, 2:2, 2:3 }
// { 1:0, 2:0, 2:0, 4:0, 2:2, 2:3 }
// { 1:0, 2:0, 2:0, 4:0, 2:1, 4:1, 2:3 }
// { 1:0, 2:0, 2:0, 4:0, 2:0, 4:0, 4:1, 2:3 }
// { 1:0, 2:0, 2:0, 4:0, 2:0, 4:0, 4:0, 8:0, 2:3 }
// { 1:0, 2:0, 2:0, 4:0, 2:0, 4:0, 4:0, 8:0, 2:2, 4:2 }
// { 1:0, 2:0, 2:0, 4:0, 2:0, 4:0, 4:0, 8:0, 2:1, 4:1, 4:2 }
// { 1:0, 2:0, 2:0, 4:0, 2:0, 4:0, 4:0, 8:0, 2:0, 4:0, 4:1, 4:2 }
// { 1:0, 2:0, 2:0, 4:0, 2:0, 4:0, 4:0, 8:0, 2:0, 4:0, 4:0, 8:0, 4:2 }
// { 1:0, 2:0, 2:0, 4:0, 2:0, 4:0, 4:0, 8:0, 2:0, 4:0, 4:0, 8:0, 4:1, 8:1 }
// { 1:0, 2:0, 2:0, 4:0, 2:0, 4:0, 4:0, 8:0, 2:0, 4:0, 4:0, 8:0, 4:0, 8:0, 8:1 }
// { 1:0, 2:0, 2:0, 4:0, 2:0, 4:0, 4:0, 8:0, 2:0, 4:0, 4:0, 8:0, 4:0, 8:0, 8:0, 16:0 }
// Thus, the final lazy list is
// { 1, 2, 2, 4, 2, 4, 4, 8, 2, 4, 4, 8, 4, 8, 8, 16 }
check(repeat_at_most(1, [](int v) { return from(v, v, 2*v); }, 4),
list<int>({ 1, 2, 2, 4, 2, 4, 4, 8, 2, 4, 4, 8, 4, 8, 8, 16 }));
}
class gen {
unsigned m_next;
public:
gen():m_next(0) {}
unsigned next() { unsigned r = m_next; m_next++; return r; }
};
lazy_list<unsigned> mk_gen(std::shared_ptr<gen> const & g) {
return mk_lazy_list<unsigned>([=]() { return some(mk_pair(g->next(), mk_gen(g))); });
}
lazy_list<unsigned> mk_gen() {
return mk_gen(std::make_shared<gen>());
}
void tst5() {
auto l = mk_gen();
display(take(10, l));
display(take(10, l));
}
void tst6() {
auto l = mk_gen();
unsigned counter = 0;
for_each(filter(take(10, l), [](unsigned v) { return v % 2 == 0; }), [&](unsigned) { counter++; });
lean_assert(counter == 5);
}
int main() {
save_stack_info();
tst1();
tst2();
tst3();
tst4();
tst5();
tst6();
return has_violations() ? 1 : 0;
}