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feat(frontends/lean/elaborator): anonymous constructor notation for ginductives

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This commit is contained in:
Sebastian Ullrich 2018-05-17 14:14:00 +02:00
parent 53d459911f
commit 696ba77b53
1 changed files with 6 additions and 7 deletions
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13
src/frontends/lean/elaborator.cpp
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@ -2109,20 +2109,19 @@ expr elaborator::visit_anonymous_constructor(expr const & e, optional<expr> cons
expr const & c = get_app_args(get_anonymous_constructor_arg(e), args);
if (!expected_type)
throw elaborator_exception(e, "invalid constructor ⟨...⟩, expected type must be known");
expr I = get_app_fn(m_ctx.relaxed_whnf(instantiate_mvars(*expected_type)));
expr I = get_app_fn(whnf_ginductive(m_ctx, instantiate_mvars(*expected_type)));
if (!is_constant(I))
throw elaborator_exception(e, format("invalid constructor ⟨...⟩, expected type is not an inductive type") +
pp_indent(*expected_type));
name I_name = const_name(I);
if (is_private(m_env, I_name) && !is_expr_aliased(m_env, I_name))
throw elaborator_exception(e, "invalid constructor ⟨...⟩, type is a private inductive datatype");
if (!inductive::is_inductive_decl(m_env, I_name))
if (!is_ginductive(m_env, I_name))
throw elaborator_exception(e, sstream() << "invalid constructor ⟨...⟩, '" << I_name << "' is not an inductive type");
buffer<name> c_names;
get_intro_rule_names(m_env, I_name, c_names);
if (c_names.size() != 1)
auto c_names = get_ginductive_intro_rules(m_env, I_name);
if (!c_names || tail(c_names))
throw elaborator_exception(e, sstream() << "invalid constructor ⟨...⟩, '" << I_name << "' must have only one constructor");
expr type = m_env.get(c_names[0]).get_type();
expr type = m_env.get(head(c_names)).get_type();
unsigned num_explicit = 0;
while (is_pi(type)) {
if (is_explicit(binding_info(type)))
@ -2136,7 +2135,7 @@ expr elaborator::visit_anonymous_constructor(expr const & e, optional<expr> cons
args.shrink(num_explicit);
args.back() = rest;
}
expr new_e = copy_tag(e, mk_app(mk_constant(c_names[0]), args));
expr new_e = copy_tag(e, mk_app(mk_constant(head(c_names)), args));
return visit(new_e, expected_type);
}