171 lines
7.3 KiB
C++
171 lines
7.3 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
|
|
*/
|
|
#include "kernel/type_checker.h"
|
|
#include "kernel/for_each_fn.h"
|
|
#include "kernel/error_msgs.h"
|
|
#include "library/util.h"
|
|
#include "library/constants.h"
|
|
#include "library/reducible.h"
|
|
#include "library/tactic/tactic.h"
|
|
#include "library/tactic/elaborate.h"
|
|
#include "library/tactic/expr_to_tactic.h"
|
|
|
|
namespace lean {
|
|
// Return true iff \c e is of the form (?m l_1 ... l_n), where ?m is a metavariable and l_i's local constants
|
|
bool is_meta_placeholder(expr const & e) {
|
|
if (!is_meta(e))
|
|
return false;
|
|
buffer<expr> args;
|
|
get_app_args(e, args);
|
|
return std::all_of(args.begin(), args.end(), is_local);
|
|
}
|
|
|
|
tactic exact_tactic(elaborate_fn const & elab, expr const & e, bool enforce_type_during_elaboration, bool allow_metavars,
|
|
bool conservative) {
|
|
return tactic01([=](environment const & env, io_state const & ios, proof_state const & s) {
|
|
proof_state new_s = s;
|
|
goals const & gs = new_s.get_goals();
|
|
if (!gs) {
|
|
throw_no_goal_if_enabled(s);
|
|
return none_proof_state();
|
|
}
|
|
expr t = head(gs).get_type();
|
|
bool report_unassigned = !allow_metavars && enforce_type_during_elaboration && s.report_failure();
|
|
optional<expr> new_e;
|
|
try {
|
|
new_e = elaborate_with_respect_to(env, ios, elab, new_s, e, some_expr(t),
|
|
report_unassigned, enforce_type_during_elaboration,
|
|
conservative);
|
|
} catch (exception &) {
|
|
if (s.report_failure())
|
|
throw;
|
|
else
|
|
return none_proof_state();
|
|
}
|
|
if (new_e) {
|
|
goals const & gs = new_s.get_goals();
|
|
if (gs) {
|
|
goal const & g = head(gs);
|
|
if (!allow_metavars && has_expr_metavar_relaxed(*new_e)) {
|
|
throw_tactic_exception_if_enabled(s, [=](formatter const & fmt) {
|
|
format r = format("invalid 'exact' tactic, term still contains metavariables "
|
|
"after elaboration");
|
|
r += pp_indent_expr(fmt, *new_e);
|
|
return r;
|
|
});
|
|
return none_proof_state();
|
|
}
|
|
substitution subst = new_s.get_subst();
|
|
assign(subst, g, *new_e);
|
|
if (allow_metavars) {
|
|
buffer<goal> new_goals;
|
|
auto tc = mk_type_checker(env);
|
|
for_each(*new_e, [&](expr const & m, unsigned) {
|
|
if (!has_expr_metavar(m))
|
|
return false;
|
|
if (is_meta_placeholder(m)) {
|
|
new_goals.push_back(goal(m, tc->infer(m).first));
|
|
return false;
|
|
}
|
|
return !is_metavar(m) && !is_local(m);
|
|
});
|
|
goals new_gs = to_list(new_goals.begin(), new_goals.end(), tail(gs));
|
|
return some(proof_state(new_s, new_gs, subst));
|
|
} else {
|
|
return some(proof_state(new_s, tail(gs), subst));
|
|
}
|
|
} else {
|
|
return some_proof_state(new_s);
|
|
}
|
|
}
|
|
return none_proof_state();
|
|
});
|
|
}
|
|
|
|
static tactic assumption_tactic_core(bool conservative) {
|
|
return tactic([=](environment const & env, io_state const & ios, proof_state const & s) {
|
|
goals const & gs = s.get_goals();
|
|
if (empty(gs)) {
|
|
throw_no_goal_if_enabled(s);
|
|
return proof_state_seq();
|
|
}
|
|
proof_state new_s = s.update_report_failure(false);
|
|
optional<tactic> tac;
|
|
goal g = head(gs);
|
|
buffer<expr> hs;
|
|
g.get_hyps(hs);
|
|
auto elab = [](goal const &, options const &, expr const & H,
|
|
optional<expr> const &, substitution const & s, bool) -> elaborate_result {
|
|
return elaborate_result(H, s, constraints());
|
|
};
|
|
unsigned i = hs.size();
|
|
while (i > 0) {
|
|
--i;
|
|
expr const & h = hs[i];
|
|
tactic curr = exact_tactic(elab, h, false, false, conservative);
|
|
if (tac) {
|
|
tac = orelse(*tac, curr);
|
|
} else {
|
|
tac = curr;
|
|
}
|
|
}
|
|
if (tac) {
|
|
return (*tac)(env, ios, s);
|
|
} else {
|
|
return proof_state_seq();
|
|
}
|
|
});
|
|
}
|
|
|
|
tactic eassumption_tactic() {
|
|
return assumption_tactic_core(false);
|
|
}
|
|
|
|
tactic assumption_tactic() {
|
|
return assumption_tactic_core(true);
|
|
}
|
|
|
|
static expr * g_exact_tac_fn = nullptr;
|
|
static expr * g_rexact_tac_fn = nullptr;
|
|
static expr * g_refine_tac_fn = nullptr;
|
|
expr const & get_exact_tac_fn() { return *g_exact_tac_fn; }
|
|
expr const & get_rexact_tac_fn() { return *g_rexact_tac_fn; }
|
|
expr const & get_refine_tac_fn() { return *g_refine_tac_fn; }
|
|
void initialize_exact_tactic() {
|
|
name const & exact_tac_name = get_tactic_exact_name();
|
|
name const & rexact_tac_name = get_tactic_rexact_name();
|
|
name const & refine_tac_name = get_tactic_refine_name();
|
|
g_exact_tac_fn = new expr(Const(exact_tac_name));
|
|
g_rexact_tac_fn = new expr(Const(rexact_tac_name));
|
|
g_refine_tac_fn = new expr(Const(refine_tac_name));
|
|
register_tac(exact_tac_name,
|
|
[](old_type_checker &, elaborate_fn const & fn, expr const & e, pos_info_provider const *) {
|
|
check_tactic_expr(app_arg(e), "invalid 'exact' tactic, invalid argument");
|
|
return exact_tactic(fn, get_tactic_expr_expr(app_arg(e)), true, false, false);
|
|
});
|
|
register_tac(rexact_tac_name,
|
|
[](old_type_checker &, elaborate_fn const & fn, expr const & e, pos_info_provider const *) {
|
|
check_tactic_expr(app_arg(e), "invalid 'rexact' tactic, invalid argument");
|
|
return exact_tactic(fn, get_tactic_expr_expr(app_arg(e)), false, false, false);
|
|
});
|
|
register_tac(refine_tac_name,
|
|
[](old_type_checker &, elaborate_fn const & fn, expr const & e, pos_info_provider const *) {
|
|
check_tactic_expr(app_arg(e), "invalid 'refine' tactic, invalid argument");
|
|
return exact_tactic(fn, get_tactic_expr_expr(app_arg(e)), true, true, false);
|
|
});
|
|
register_simple_tac(get_tactic_eassumption_name(),
|
|
[]() { return eassumption_tactic(); });
|
|
|
|
register_simple_tac(get_tactic_assumption_name(),
|
|
[]() { return assumption_tactic(); });
|
|
}
|
|
void finalize_exact_tactic() {
|
|
delete g_exact_tac_fn;
|
|
delete g_rexact_tac_fn;
|
|
delete g_refine_tac_fn;
|
|
}
|
|
}
|