blob: f9f562ae4f489136c2457d4f45b9cc32f907f964 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
/*
* richard-atp-engine: A saturation-based automated theorem prover for first-order logic.
* Copyright (C) 2026 Richard Qin
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#pragma once
/// @file substitution.h
/// @brief Variable binding map: Var -> Term.
#include "atp/core/types.h"
#include <vector>
namespace atp {
/// A substitution is a mapping from variable TermIds to their bound TermIds.
/// Designed as a short-lived, stack-allocated object during unification.
class Substitution {
public:
Substitution() = default;
/// Bind a variable to a term. Returns false if already bound to something different.
bool bind(TermId var, TermId term);
/// Look up what a variable is bound to. Returns kInvalidId if unbound.
[[nodiscard]] TermId lookup(TermId var) const;
/// Walk the binding chain to the final bound value.
[[nodiscard]] TermId resolve(TermId id) const;
/// Clear all bindings.
void clear();
private:
// TODO: Phase 2 implementation
std::vector<std::pair<TermId, TermId>> bindings_;
};
} // namespace atp
|
