lean2/src/library/blast/intros.cpp

40 lines
1.2 KiB
C++

/*
Copyright (c) 2015 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.
Author: Leonardo de Moura
*/
#include "kernel/abstract.h"
#include "kernel/instantiate.h"
#include "library/blast/blast.h"
#include "library/blast/proof_expr.h"
namespace lean {
namespace blast {
struct intros_proof_step_cell : public proof_step_cell {
list<expr> m_new_hs;
virtual ~intros_proof_step_cell() {}
virtual optional<expr> resolve(state & s, expr const & pr) const {
expr new_pr = mk_proof_lambda(s, m_new_hs, unfold_hypotheses_ge(s, pr));
return some_expr(new_pr);
}
};
bool intros_action() {
state & s = curr_state();
expr target = whnf(s.get_target());
if (!is_pi(target))
return false;
auto pcell = new intros_proof_step_cell();
s.push_proof_step(proof_step(pcell));
buffer<expr> new_hs;
while (is_pi(target)) {
expr href = s.mk_hypothesis(binding_name(target), binding_domain(target));
new_hs.push_back(href);
target = whnf(instantiate(binding_body(target), href));
}
pcell->m_new_hs = to_list(new_hs);
s.set_target(target);
return true;
}
}}