/* 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 "util/sstream.h" #include "kernel/abstract.h" #include "library/annotation.h" #include "library/placeholder.h" #include "library/explicit.h" #include "library/aliases.h" #include "library/scoped_ext.h" #include "library/tactic/tactic.h" #include "library/tactic/expr_to_tactic.h" #include "library/tactic/exact_tactic.h" #include "library/tactic/util.h" #include "library/typed_expr.h" #include "library/choice.h" #include "library/let.h" #include "library/constants.h" #include "library/definitional/equations.h" #include "library/tactic/assert_tactic.h" #include "frontends/lean/builtin_exprs.h" #include "frontends/lean/decl_cmds.h" #include "frontends/lean/token_table.h" #include "frontends/lean/calc.h" #include "frontends/lean/begin_end_ext.h" #include "frontends/lean/parser.h" #include "frontends/lean/util.h" #include "frontends/lean/tokens.h" #include "frontends/lean/info_tactic.h" #include "frontends/lean/info_annotation.h" #include "frontends/lean/structure_cmd.h" #include "frontends/lean/parse_rewrite_tactic.h" namespace lean { namespace notation { static expr parse_Type(parser & p, unsigned, expr const *, pos_info const & pos) { if (p.curr_is_token(get_llevel_curly_tk())) { p.next(); level l = p.parse_level(); p.check_token_next(get_rcurly_tk(), "invalid Type expression, '}' expected"); return p.save_pos(mk_sort(l), pos); } else { return p.save_pos(mk_sort(mk_level_placeholder()), pos); } } static expr parse_let(parser & p, pos_info const & pos); static expr parse_let_body(parser & p, pos_info const & pos) { if (p.curr_is_token(get_comma_tk())) { p.next(); return parse_let(p, pos); } else if (p.curr_is_token(get_in_tk())) { p.next(); return p.parse_expr(); } else { throw parser_error("invalid let declaration, 'in' or ',' expected", p.pos()); } } static void parse_let_modifiers(parser & p, bool & is_visible) { while (true) { if (p.curr_is_token(get_visible_tk())) { is_visible = true; p.next(); } else { break; } } } static expr parse_let(parser & p, pos_info const & pos) { parser::local_scope scope1(p); if (p.parse_local_notation_decl()) { return parse_let_body(p, pos); } else { auto id_pos = p.pos(); name id = p.check_atomic_id_next("invalid let declaration, identifier expected"); bool is_visible = false; optional type; expr value; parse_let_modifiers(p, is_visible); if (p.curr_is_token(get_assign_tk())) { p.next(); value = p.parse_expr(); } else if (p.curr_is_token(get_colon_tk())) { p.next(); type = p.parse_expr(); p.check_token_next(get_assign_tk(), "invalid declaration, ':=' expected"); value = p.parse_expr(); } else { parser::local_scope scope2(p); buffer ps; unsigned rbp = 0; auto lenv = p.parse_binders(ps, rbp); if (p.curr_is_token(get_colon_tk())) { p.next(); type = p.parse_scoped_expr(ps, lenv); type = Pi(ps, *type, p); } p.check_token_next(get_assign_tk(), "invalid let declaration, ':=' expected"); value = p.parse_scoped_expr(ps, lenv); value = Fun(ps, value, p); } expr v; if (type) v = p.save_pos(mk_typed_expr(*type, value), p.pos_of(value)); else v = value; v = p.save_pos(mk_let_value(v), id_pos); p.add_local_expr(id, v); expr b = parse_let_body(p, pos); return p.save_pos(mk_let(id, v, b), pos); } } static expr parse_let_expr(parser & p, unsigned, expr const *, pos_info const & pos) { return parse_let(p, pos); } static expr parse_placeholder(parser & p, unsigned, expr const *, pos_info const & pos) { return p.save_pos(mk_explicit_expr_placeholder(), pos); } static expr parse_by(parser & p, unsigned, expr const *, pos_info const & pos) { parser::undef_id_to_local_scope scope(p); p.next(); expr t = p.parse_tactic(); return p.mk_by(t, pos); } static expr parse_begin_end_core(parser & p, pos_info const & pos, name const & end_token, bool nested = false) { if (!p.has_tactic_decls()) throw parser_error("invalid 'begin-end' expression, tactic module has not been imported", pos); parser::undef_id_to_local_scope scope1(p); p.next(); optional pre_tac = get_begin_end_pre_tactic(p.env()); buffer tacs; bool first = true; auto add_tac = [&](expr tac, pos_info const & pos) { if (pre_tac) tac = p.mk_app({get_and_then_tac_fn(), *pre_tac, tac}, pos); tac = mk_begin_end_element_annotation(tac); tacs.push_back(tac); }; while (!p.curr_is_token(end_token)) { if (first) { first = false; } else { auto pos = p.pos(); p.check_token_next(get_comma_tk(), "invalid 'begin-end' expression, ',' expected"); if (p.collecting_info()) { expr info_tac = p.save_pos(mk_info_tactic_expr(), pos); tacs.push_back(mk_begin_end_element_annotation(info_tac)); } } if (p.curr_is_token(get_begin_tk())) { auto pos = p.pos(); tacs.push_back(parse_begin_end_core(p, pos, get_end_tk(), true)); } else if (p.curr_is_token(get_lcurly_tk())) { auto pos = p.pos(); tacs.push_back(parse_begin_end_core(p, pos, get_rcurly_tk(), true)); } else if (p.curr_is_token(end_token)) { break; } else if (p.curr_is_token(get_assert_tk())) { auto pos = p.pos(); p.next(); name id = p.check_id_next("invalid 'assert' tactic, identifier expected"); p.check_token_next(get_colon_tk(), "invalid 'assert' tactic, ':' expected"); expr A = p.parse_expr(); expr assert_tac = p.save_pos(mk_assert_tactic_expr(id, A), pos); tacs.push_back(mk_begin_end_element_annotation(assert_tac)); } else if (p.curr_is_token(get_have_tk())) { auto pos = p.pos(); p.next(); name id = p.check_id_next("invalid 'have' tactic, identifier expected"); p.check_token_next(get_colon_tk(), "invalid 'have' tactic, ':' expected"); expr A = p.parse_expr(); p.check_token_next(get_comma_tk(), "invalid 'have' tactic, ',' expected"); expr assert_tac = p.save_pos(mk_assert_tactic_expr(id, A), pos); tacs.push_back(mk_begin_end_element_annotation(assert_tac)); if (p.curr_is_token(get_from_tk())) { // parse: 'from' expr p.next(); auto pos = p.pos(); expr t = p.parse_expr(); t = p.mk_app(get_exact_tac_fn(), t, pos); t = p.save_pos(mk_begin_end_element_annotation(t), pos); t = p.save_pos(mk_begin_end_annotation(t), pos); add_tac(t, pos); } else if (p.curr_is_token(get_proof_tk())) { auto pos = p.pos(); p.next(); expr t = p.parse_expr(); p.check_token_next(get_qed_tk(), "invalid proof-qed, 'qed' expected"); t = p.mk_app(get_exact_tac_fn(), t, pos); t = p.save_pos(mk_begin_end_element_annotation(t), pos); t = p.save_pos(mk_begin_end_annotation(t), pos); add_tac(t, pos); } else if (p.curr_is_token(get_begin_tk())) { auto pos = p.pos(); tacs.push_back(parse_begin_end_core(p, pos, get_end_tk(), true)); } else if (p.curr_is_token(get_by_tk())) { // parse: 'by' tactic auto pos = p.pos(); p.next(); expr t = p.parse_tactic(); add_tac(t, pos); } else { throw parser_error("invalid 'have' tactic, 'by', 'begin', 'proof', or 'from' expected", p.pos()); } } else if (p.curr_is_token(get_show_tk()) || p.curr_is_token(get_assume_tk()) || p.curr_is_token(get_take_tk()) || p.curr_is_token(get_fun_tk())) { auto pos = p.pos(); expr t = p.parse_expr(); t = p.mk_app(get_exact_tac_fn(), t, pos); add_tac(t, pos); } else { auto pos = p.pos(); expr t = p.parse_tactic(); add_tac(t, pos); } } auto end_pos = p.pos(); p.next(); if (tacs.empty()) { expr tac = get_id_tac_fn(); if (pre_tac) tac = p.mk_app({get_and_then_tac_fn(), *pre_tac, tac}, end_pos); tac = mk_begin_end_element_annotation(tac); tacs.push_back(tac); } expr r = tacs[0]; if (tacs.size() == 1) { // Hack: for having a uniform squiggle placement for unsolved goals. // That is, the result is always of the form and_then(...). r = p.mk_app({get_and_then_tac_fn(), r, mk_begin_end_element_annotation(get_id_tac_fn())}, end_pos); } for (unsigned i = 1; i < tacs.size(); i++) { r = p.mk_app({get_and_then_tac_fn(), r, tacs[i]}, end_pos); } r = p.save_pos(mk_begin_end_annotation(r), end_pos); if (nested) return r; else return p.mk_by(r, end_pos); } static expr parse_begin_end(parser & p, unsigned, expr const *, pos_info const & pos) { return parse_begin_end_core(p, pos, get_end_tk()); } static expr parse_proof_qed_core(parser & p, pos_info const & pos) { expr r = p.parse_expr(); p.check_token_next(get_qed_tk(), "invalid proof-qed, 'qed' expected"); r = p.mk_by(p.mk_app(get_exact_tac_fn(), r, pos), pos); return r; } static expr parse_proof(parser & p, expr const & prop) { if (p.curr_is_token(get_from_tk())) { // parse: 'from' expr p.next(); return p.parse_expr(); } else if (p.curr_is_token(get_proof_tk())) { auto pos = p.pos(); p.next(); return parse_proof_qed_core(p, pos); } else if (p.curr_is_token(get_begin_tk())) { auto pos = p.pos(); return parse_begin_end_core(p, pos, get_end_tk()); } else if (p.curr_is_token(get_by_tk())) { // parse: 'by' tactic auto pos = p.pos(); p.next(); expr t = p.parse_tactic(); return p.mk_by(t, pos); } else if (p.curr_is_token(get_using_tk())) { // parse: 'using' locals* ',' proof auto using_pos = p.pos(); p.next(); parser::local_scope scope(p); buffer locals; buffer new_locals; while (!p.curr_is_token(get_comma_tk())) { auto id_pos = p.pos(); expr l = p.parse_expr(); if (!is_local(l)) throw parser_error("invalid 'using' declaration for 'have', local expected", id_pos); expr new_l = l; binder_info bi = local_info(l); if (!bi.is_contextual()) new_l = update_local(l, bi.update_contextual(true)); p.add_local(new_l); locals.push_back(l); new_locals.push_back(new_l); } p.next(); // consume ',' expr pr = parse_proof(p, prop); unsigned i = locals.size(); while (i > 0) { --i; expr l = locals[i]; expr new_l = new_locals[i]; pr = p.save_pos(Fun(new_l, pr), using_pos); pr = p.save_pos(mk_app(pr, l), using_pos); } return pr; } else { throw parser_error("invalid expression, 'by', 'begin', 'proof', 'using' or 'from' expected", p.pos()); } } static expr parse_have_core(parser & p, pos_info const & pos, optional const & prev_local, bool is_visible) { auto id_pos = p.pos(); name id; expr prop; if (p.curr_is_token(get_visible_tk())) { p.next(); is_visible = true; id = p.mk_fresh_name(); prop = p.parse_expr(); } else if (p.curr_is_identifier()) { id = p.get_name_val(); p.next(); if (p.curr_is_token(get_visible_tk())) { p.next(); p.check_token_next(get_colon_tk(), "invalid 'have/assert' declaration, ':' expected"); is_visible = true; prop = p.parse_expr(); } else if (p.curr_is_token(get_colon_tk())) { p.next(); prop = p.parse_expr(); } else { expr left = p.id_to_expr(id, id_pos); id = p.mk_fresh_name(); prop = p.parse_led(left); } } else { id = p.mk_fresh_name(); prop = p.parse_expr(); } p.check_token_next(get_comma_tk(), "invalid 'have/assert' declaration, ',' expected"); expr proof; if (prev_local) { parser::local_scope scope(p); p.add_local(*prev_local); auto proof_pos = p.pos(); proof = parse_proof(p, prop); proof = p.save_pos(Fun(*prev_local, proof), proof_pos); proof = p.save_pos(mk_app(proof, *prev_local), proof_pos); } else { proof = parse_proof(p, prop); } p.check_token_next(get_comma_tk(), "invalid 'have/assert' declaration, ',' expected"); parser::local_scope scope(p); binder_info bi = mk_contextual_info(is_visible); expr l = p.save_pos(mk_local(id, prop, bi), pos); p.add_local(l); expr body; if (p.curr_is_token(get_then_tk())) { auto then_pos = p.pos(); p.next(); if (p.curr_is_token(get_assert_tk())) { p.next(); is_visible = true; } else { p.check_token_next(get_have_tk(), "invalid 'then' declaration, 'have' or 'assert' expected"); is_visible = false; } body = parse_have_core(p, then_pos, some_expr(l), is_visible); } else { body = p.parse_expr(); } // remark: mk_contextual_info(false) informs the elaborator that prop should not occur inside metavariables. body = abstract(body, l); expr r = p.save_pos(mk_have_annotation(p.save_pos(mk_lambda(id, prop, body, bi), pos)), pos); return p.mk_app(r, proof, pos); } static expr parse_have(parser & p, unsigned, expr const *, pos_info const & pos) { return parse_have_core(p, pos, none_expr(), false); } static expr parse_assert(parser & p, unsigned, expr const *, pos_info const & pos) { return parse_have_core(p, pos, none_expr(), true); } static name * H_show = nullptr; static expr parse_show(parser & p, unsigned, expr const *, pos_info const & pos) { expr prop = p.parse_expr(); p.check_token_next(get_comma_tk(), "invalid 'show' declaration, ',' expected"); expr proof = parse_proof(p, prop); expr b = p.save_pos(mk_lambda(*H_show, prop, Var(0)), pos); expr r = p.mk_app(b, proof, pos); return p.save_pos(mk_show_annotation(r), pos); } static expr parse_obtain(parser & p, unsigned, expr const *, pos_info const & pos) { if (!p.env().find(get_exists_elim_name())) throw parser_error("invalid use of 'obtain' expression, environment does not contain 'exists.elim' theorem", pos); // exists_elim {A : Type} {P : A → Prop} {B : Prop} (H1 : ∃ x : A, P x) (H2 : ∀ (a : A) (H : P a), B) buffer ps; auto b_pos = p.pos(); unsigned rbp = 0; environment env = p.parse_binders(ps, rbp); unsigned num_ps = ps.size(); if (num_ps < 2) throw parser_error("invalid 'obtain' expression, at least 2 binders expected", b_pos); p.check_token_next(get_comma_tk(), "invalid 'obtain' expression, ',' expected"); p.check_token_next(get_from_tk(), "invalid 'obtain' expression, 'from' expected"); expr H1 = p.parse_expr(); p.check_token_next(get_comma_tk(), "invalid 'obtain' expression, ',' expected"); expr b = p.parse_scoped_expr(ps, env); expr H = ps[num_ps-1]; name H_name = local_pp_name(H); unsigned i = num_ps-1; while (i > 1) { --i; expr a = ps[i]; expr H_aux = mk_local(p.mk_fresh_name(), H_name.append_after(i), mk_expr_placeholder(), mk_contextual_info(false)); expr H2 = Fun({a, H}, b); b = mk_app(mk_constant(get_exists_elim_name()), H_aux, H2); H = H_aux; } expr a = ps[0]; expr H2 = Fun({a, H}, b); expr r = mk_app(mk_constant(get_exists_elim_name()), H1, H2); return p.rec_save_pos(r, pos); } static expr * g_not = nullptr; static unsigned g_then_else_prec = 45; static expr parse_ite(parser & p, expr const & c, pos_info const & pos) { if (!p.env().find(get_ite_name())) throw parser_error("invalid use of 'if-then-else' expression, environment does not contain 'ite' definition", pos); p.check_token_next(get_then_tk(), "invalid 'if-then-else' expression, 'then' expected"); expr t = p.parse_expr(g_then_else_prec); p.check_token_next(get_else_tk(), "invalid 'if-then-else' expression, 'else' expected"); expr e = p.parse_expr(g_then_else_prec); return p.save_pos(mk_app(mk_constant(get_ite_name()), c, t, e), pos); } static expr parse_dite(parser & p, name const & H_name, expr const & c, pos_info const & pos) { p.check_token_next(get_then_tk(), "invalid 'if-then-else' expression, 'then' expected"); expr t, e; { parser::local_scope scope(p); expr H = mk_local(H_name, c); p.add_local(H); auto pos = p.pos(); t = p.save_pos(Fun(H, p.parse_expr(g_then_else_prec)), pos); } p.check_token_next(get_else_tk(), "invalid 'if-then-else' expression, 'else' expected"); { parser::local_scope scope(p); expr H = mk_local(H_name, mk_app(*g_not, c)); p.add_local(H); auto pos = p.pos(); e = p.save_pos(Fun(H, p.parse_expr(g_then_else_prec)), pos); } return p.save_pos(mk_app(p.save_pos(mk_constant(get_dite_name()), pos), c, t, e), pos); } static expr parse_if_then_else(parser & p, unsigned, expr const *, pos_info const & pos) { pair, expr> ie = p.parse_qualified_expr(); if (ie.first) return parse_dite(p, *ie.first, ie.second, pos); else return parse_ite(p, ie.second, pos); } static expr parse_calc_expr(parser & p, unsigned, expr const *, pos_info const &) { return parse_calc(p); } static expr parse_rewrite_tactic_expr(parser & p, unsigned, expr const *, pos_info const & pos) { return p.save_pos(parse_rewrite_tactic(p), pos); } static expr parse_esimp_tactic_expr(parser & p, unsigned, expr const *, pos_info const & pos) { return p.save_pos(parse_esimp_tactic(p), pos); } static expr parse_overwrite_notation(parser & p, unsigned, expr const *, pos_info const &) { name n = p.check_id_next("invalid '#' local notation, identifier expected"); environment env = overwrite_notation(p.env(), n); return p.parse_scoped_expr(0, nullptr, env); } static expr parse_explicit_expr(parser & p, unsigned, expr const *, pos_info const & pos) { expr e = p.parse_expr(get_Max_prec()); if (is_choice(e)) { buffer new_choices; for (unsigned i = 0; i < get_num_choices(e); i++) new_choices.push_back(p.save_pos(mk_explicit(get_choice(e, i)), pos)); return p.save_pos(mk_choice(new_choices.size(), new_choices.data()), pos); } else { return p.save_pos(mk_explicit(e), pos); } } static expr parse_consume_args_expr(parser & p, unsigned, expr const *, pos_info const & pos) { expr e = p.parse_expr(get_Max_prec()); if (is_choice(e)) { buffer new_choices; for (unsigned i = 0; i < get_num_choices(e); i++) new_choices.push_back(p.save_pos(mk_consume_args(get_choice(e, i)), pos)); return p.save_pos(mk_choice(new_choices.size(), new_choices.data()), pos); } else { return p.save_pos(mk_consume_args(e), pos); } } static expr parse_sorry(parser & p, unsigned, expr const *, pos_info const & pos) { return p.mk_sorry(pos); } static expr parse_rparen(parser & p, unsigned, expr const * args, pos_info const & pos) { if (p.collecting_info()) return p.save_pos(mk_extra_info(args[0], nulltag), pos); else return args[0]; } static expr parse_proof_qed(parser & p, unsigned, expr const *, pos_info const & pos) { return parse_proof_qed_core(p, pos); } static expr parse_inaccessible(parser & p, unsigned, expr const * args, pos_info const & pos) { return p.save_pos(mk_inaccessible(args[0]), pos); } parse_table init_nud_table() { action Expr(mk_expr_action()); action Skip(mk_skip_action()); action Binders(mk_binders_action()); expr x0 = mk_var(0); parse_table r; r = r.add({transition("_", mk_ext_action(parse_placeholder))}, x0); r = r.add({transition("by", mk_ext_action_core(parse_by))}, x0); r = r.add({transition("have", mk_ext_action(parse_have))}, x0); r = r.add({transition("assert", mk_ext_action(parse_assert))}, x0); r = r.add({transition("show", mk_ext_action(parse_show))}, x0); r = r.add({transition("obtain", mk_ext_action(parse_obtain))}, x0); r = r.add({transition("if", mk_ext_action(parse_if_then_else))}, x0); r = r.add({transition("(", Expr), transition(")", mk_ext_action(parse_rparen))}, x0); r = r.add({transition("?(", Expr), transition(")", mk_ext_action(parse_inaccessible))}, x0); r = r.add({transition("⌞", Expr), transition("⌟", mk_ext_action(parse_inaccessible))}, x0); r = r.add({transition("fun", Binders), transition(",", mk_scoped_expr_action(x0))}, x0); r = r.add({transition("Pi", Binders), transition(",", mk_scoped_expr_action(x0, 0, false))}, x0); r = r.add({transition("Type", mk_ext_action(parse_Type))}, x0); r = r.add({transition("let", mk_ext_action(parse_let_expr))}, x0); r = r.add({transition("calc", mk_ext_action(parse_calc_expr))}, x0); r = r.add({transition("rewrite", mk_ext_action(parse_rewrite_tactic_expr))}, x0); r = r.add({transition("esimp", mk_ext_action(parse_esimp_tactic_expr))}, x0); r = r.add({transition("#", mk_ext_action(parse_overwrite_notation))}, x0); r = r.add({transition("@", mk_ext_action(parse_explicit_expr))}, x0); r = r.add({transition("!", mk_ext_action(parse_consume_args_expr))}, x0); r = r.add({transition("begin", mk_ext_action_core(parse_begin_end))}, x0); r = r.add({transition("proof", mk_ext_action(parse_proof_qed))}, x0); r = r.add({transition("sorry", mk_ext_action(parse_sorry))}, x0); r = r.add({transition("match", mk_ext_action(parse_match))}, x0); init_structure_instance_parsing_rules(r); return r; } parse_table init_led_table() { parse_table r(false); r = r.add({transition("->", mk_expr_action(get_arrow_prec()-1))}, mk_arrow(Var(1), Var(1))); r = r.add({transition("