27 lines
961 B
C++
27 lines
961 B
C++
/*
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Copyright (c) 2014 Microsoft Corporation. All rights reserved.
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Released under Apache 2.0 license as described in the file LICENSE.
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Author: Leonardo de Moura
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*/
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#include "frontends/lean/choice_iterator.h"
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namespace lean {
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lazy_list<constraints> choose(std::shared_ptr<choice_iterator> c, bool ignore_failure) {
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return mk_lazy_list<constraints>([=]() {
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auto s = c->next();
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if (s) {
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return some(mk_pair(*s, choose(c, false)));
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} else if (ignore_failure) {
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// return singleton empty list of constraints, and let tactic hints try to instantiate the metavariable.
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return lazy_list<constraints>::maybe_pair(constraints(), lazy_list<constraints>());
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} else {
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return lazy_list<constraints>::maybe_pair();
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}
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});
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}
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lazy_list<constraints> choose(std::shared_ptr<choice_iterator> c) {
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return choose(c, c->ignore_failure());
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}
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}
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