feat(library/blast): classical flag

src/library/blast/blast.cpp

@@ -13,12 +13,14 @@ Author: Leonardo de Moura
 #include "library/util.h"
 #include "library/reducible.h"
 #include "library/class.h"
+#include "library/constants.h"
 #include "library/type_context.h"
 #include "library/relation_manager.h"
 #include "library/congr_lemma_manager.h"
 #include "library/abstract_expr_manager.h"
 #include "library/light_lt_manager.h"
 #include "library/projection.h"
+#include "library/scoped_ext.h"
 #include "library/tactic/goal.h"
 #include "library/blast/expr.h"
 #include "library/blast/state.h"
@@ -69,6 +71,7 @@ class blastenv {
     symm_info_getter           m_symm_getter;
     trans_info_getter          m_trans_getter;
     unfold_macro_pred          m_unfold_macro_pred;
+    bool                       m_classical{false};
 
     class tctx : public type_context {
         blastenv &                              m_benv;
@@ -462,8 +465,18 @@ public:
             delete ctx;
     }
 
+    void init_classical_flag() {
+        for_each(get_namespaces(m_env), [&](name const & ns) {
+                if (m_classical) return;
+                if (ns == get_classical_name()) m_classical = true;
+            });
+    }
+
+    bool classical() { return m_classical; }
+
     void init_state(goal const & g) {
         init_curr_state(g);
+        init_classical_flag();
         save_initial_context();
         m_tctx.set_local_instances(m_initial_context);
         m_tmp_ctx->set_local_instances(m_initial_context);
@@ -788,6 +801,11 @@ bool is_light_lt(expr const & e1, expr const & e2) {
     return g_blastenv->is_light_lt(e1, e2);
 }
 
+bool classical() {
+    lean_assert(g_blastenv);
+    return g_blastenv->classical();
+}
+
 void display_curr_state() {
     curr_state().display(env(), ios());
     display("\n");

src/library/blast/blast.h

@@ -118,6 +118,9 @@ bool abstract_is_equal(expr const & e1, expr const & e2);
 /** \brief Order on expressions that supports the "light" annotation */
 bool is_light_lt(expr const & e1, expr const & e2);
 
+/** \brief Whether [classical] namespace is open. */
+bool classical();
+
 /** \brief Display the current state of the blast tactic in the diagnostic channel. */
 void display_curr_state();
 /** \brief Display the given expression in the diagnostic channel. */

src/library/constants.cpp

@@ -19,6 +19,7 @@ name const * g_bool_ff = nullptr;
 name const * g_bool_tt = nullptr;
 name const * g_char = nullptr;
 name const * g_char_mk = nullptr;
+name const * g_classical = nullptr;
 name const * g_congr = nullptr;
 name const * g_congr_arg = nullptr;
 name const * g_congr_fun = nullptr;
@@ -196,6 +197,7 @@ void initialize_constants() {
     g_bool_tt = new name{"bool", "tt"};
     g_char = new name{"char"};
     g_char_mk = new name{"char", "mk"};
+    g_classical = new name{"classical"};
     g_congr = new name{"congr"};
     g_congr_arg = new name{"congr_arg"};
     g_congr_fun = new name{"congr_fun"};
@@ -374,6 +376,7 @@ void finalize_constants() {
     delete g_bool_tt;
     delete g_char;
     delete g_char_mk;
+    delete g_classical;
     delete g_congr;
     delete g_congr_arg;
     delete g_congr_fun;
@@ -551,6 +554,7 @@ name const & get_bool_ff_name() { return *g_bool_ff; }
 name const & get_bool_tt_name() { return *g_bool_tt; }
 name const & get_char_name() { return *g_char; }
 name const & get_char_mk_name() { return *g_char_mk; }
+name const & get_classical_name() { return *g_classical; }
 name const & get_congr_name() { return *g_congr; }
 name const & get_congr_arg_name() { return *g_congr_arg; }
 name const & get_congr_fun_name() { return *g_congr_fun; }

src/library/constants.h

@@ -21,6 +21,7 @@ name const & get_bool_ff_name();
 name const & get_bool_tt_name();
 name const & get_char_name();
 name const & get_char_mk_name();
+name const & get_classical_name();
 name const & get_congr_name();
 name const & get_congr_arg_name();
 name const & get_congr_fun_name();

src/library/constants.txt

@@ -14,6 +14,7 @@ bool.ff
 bool.tt
 char
 char.mk
+classical
 congr
 congr_arg
 congr_fun