lean2/src/library/head_map.h

93 lines
3 KiB
C++

/*
Copyright (c) 2014 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Author: Leonardo de Moura
*/
#pragma once
#include "util/rb_map.h"
#include "util/list.h"
#include "kernel/expr.h"
#include "library/io_state_stream.h"
namespace lean {
struct head_index {
expr_kind m_kind;
name m_name;
explicit head_index(expr_kind k = expr_kind::Var):m_kind(k) {}
explicit head_index(name const & c):m_kind(expr_kind::Constant), m_name(c) {}
head_index(expr const & e);
struct cmp {
int operator()(head_index const & i1, head_index const & i2) const;
};
friend std::ostream & operator<<(std::ostream & out, head_index const & head_idx);
};
/**
\brief Very simple indexing data-structure that allow us to map the head symbol of an expression to
a list of values.
The index is the expression kind and a name (if it is a constant).
This index is very naive, but it is effective for many applications.
*/
template<typename V, typename GetPrio>
class head_map_prio : private GetPrio {
rb_map<head_index, list<V>, head_index::cmp> m_map;
unsigned get_priority(V const & v) const { return GetPrio::operator()(v); }
list<V> insert_prio(V const & v, list<V> const & vs) {
if (!vs)
return to_list(v);
else if (get_priority(v) >= get_priority(head(vs)))
return cons(v, vs);
else
return cons(head(vs), insert_prio(v, tail(vs)));
}
public:
head_map_prio() {}
head_map_prio(GetPrio const & g):GetPrio(g) {}
bool empty() const { return m_map.empty(); }
bool contains(head_index const & h) const { return m_map.contains(h); }
list<V> const * find(head_index const & h) const { return m_map.find(h); }
void erase(head_index const & h) { m_map.erase(h); }
template<typename P> void filter(head_index const & h, P && p) {
if (auto it = m_map.find(h)) {
auto new_vs = ::lean::filter(*it, std::forward<P>(p));
if (!new_vs)
m_map.erase(h);
else
m_map.insert(h, new_vs);
}
}
void erase(head_index const & h, V const & v) {
return filter(h, [&](V const & v2) { return v != v2; });
}
void insert(head_index const & h, V const & v) {
if (auto it = m_map.find(h))
m_map.insert(h, insert_prio(v, ::lean::filter(*it, [&](V const & v2) { return v != v2; })));
else
m_map.insert(h, to_list(v));
}
template<typename F> void for_each(F && f) const { m_map.for_each(f); }
template<typename F> void for_each_entry(F && f) const {
m_map.for_each([&](head_index const & h, list<V> const & vs) {
for (V const & v : vs)
f(h, v);
});
}
};
template<typename V>
struct constant_priority_fn { unsigned operator()(V const &) const { return 0; } };
template<typename V>
class head_map : public head_map_prio<V, constant_priority_fn<V>> {
public:
head_map() {}
};
}