lean2/src/frontends/lean/local_decls.h

54 lines
1.8 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 <utility>
#include "util/rb_map.h"
#include "util/name.h"
#include "util/list.h"
#include "util/pair.h"
namespace lean {
/**
\brief A "scoped" map from name to values.
It also supports the operation \c find_idx that returns "when a declaration was inserted into the map".
*/
template<typename V>
class local_decls {
typedef rb_map<name, pair<V, unsigned>, name_quick_cmp> map;
typedef list<std::tuple<map, unsigned, list<V>>> scopes;
map m_map;
unsigned m_counter;
scopes m_scopes;
list<V> m_values;
public:
local_decls():m_counter(1) {}
local_decls(local_decls const & d):m_map(d.m_map), m_counter(d.m_counter), m_scopes(d.m_scopes) {}
void insert(name const & k, V const & v) {
m_map.insert(k, mk_pair(v, m_counter));
m_counter++;
m_values = cons(v, m_values);
}
V const * find(name const & k) const { auto it = m_map.find(k); return it ? &(it->first) : nullptr; }
unsigned find_idx(name const & k) const { auto it = m_map.find(k); return it ? it->second : 0; }
bool contains(name const & k) const { return m_map.contains(k); }
list<V> const & get_values() const { return m_values; }
void push() { m_scopes = scopes(std::make_tuple(m_map, m_counter, m_values), m_scopes); }
void pop() {
lean_assert(!is_nil(m_scopes));
m_map = std::get<0>(head(m_scopes));
m_counter = std::get<1>(head(m_scopes));
m_values = std::get<2>(head(m_scopes));
m_scopes = tail(m_scopes);
}
struct mk_scope {
local_decls & m_d;
mk_scope(local_decls & d):m_d(d) { m_d.push(); }
~mk_scope() { m_d.pop(); }
};
};
}