fix #1908

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

src/ast/array_decl_plugin.cpp

@@ -253,7 +253,10 @@ func_decl* array_decl_plugin::mk_select(unsigned arity, sort * const * domain) {
         if (!parameters[i].is_ast() || 
             !is_sort(parameters[i].get_ast()) || 
             !m_manager->compatible_sorts(domain[i+1], to_sort(parameters[i].get_ast()))) {
-            m_manager->raise_exception("domain sort and parameter do not match");
+            std::stringstream strm;
+            strm << "domain sort " << sort_ref(domain[i+1], *m_manager) << " and parameter ";
+            strm << parameter_pp(parameters[i], *m_manager) << " do not match";
+            m_manager->raise_exception(strm.str().c_str());
             UNREACHABLE();
             return nullptr;
         }
@@ -292,8 +295,12 @@ func_decl * array_decl_plugin::mk_store(unsigned arity, sort * const * domain) {
             m_manager->raise_exception("expecting sort parameter");
             return nullptr;
         }
-        if (!m_manager->compatible_sorts(to_sort(parameters[i].get_ast()), domain[i+1])) {
-            m_manager->raise_exception("domain sort and parameter do not match");
+        sort* srt1 = to_sort(parameters[i].get_ast());
+        sort* srt2 = domain[i+1];
+        if (!m_manager->compatible_sorts(srt1, srt2)) {
+            std::stringstream strm;
+            strm << "domain sort " << sort_ref(srt2, *m_manager) << " and parameter sort " << sort_ref(srt2, *m_manager) << " do not match";
+            m_manager->raise_exception(strm.str());
             UNREACHABLE();
             return nullptr;
         }
@@ -326,13 +333,13 @@ bool array_decl_plugin::check_set_arguments(unsigned arity, sort * const * domai
         if (domain[i] != domain[0]) {
             std::ostringstream buffer;
             buffer << "arguments " << 1 << " and " << (i+1) << " have different sorts";
-            m_manager->raise_exception(buffer.str().c_str());
+            m_manager->raise_exception(buffer.str());
             return false;
         }
         if (domain[i]->get_family_id() != m_family_id) {
             std::ostringstream buffer;
             buffer << "argument " << (i+1) << " is not of array sort";
-            m_manager->raise_exception(buffer.str().c_str());
+            m_manager->raise_exception(buffer.str());
             return false;
         }
     }
@@ -517,6 +524,7 @@ func_decl * array_decl_plugin::mk_func_decl(decl_kind k, unsigned num_parameters
 
 void array_decl_plugin::get_sort_names(svector<builtin_name>& sort_names, symbol const & logic) {
     sort_names.push_back(builtin_name(ARRAY_SORT_STR, ARRAY_SORT));
+    sort_names.push_back(builtin_name("=>", ARRAY_SORT));
     // TBD: this could easily break users even though it is already used in CVC4: 
     // sort_names.push_back(builtin_name("Set", _SET_SORT));
 }

src/ast/ast.cpp

@@ -1542,6 +1542,16 @@ void ast_manager::raise_exception(char const * msg) {
 }
 
 
+std::ostream& ast_manager::display(std::ostream& out, parameter const& p) {
+    switch (p.get_kind()) {
+    case parameter::PARAM_AST:
+        return out << mk_pp(p.get_ast(), *this);
+    default:
+        return p.display(out);
+    }
+    return out;
+}
+
 void ast_manager::copy_families_plugins(ast_manager const & from) {
     TRACE("copy_families_plugins",
           tout << "target:\n";

src/ast/ast.h

@@ -1558,6 +1558,9 @@ public:
 
     // Equivalent to throw ast_exception(msg)
     Z3_NORETURN void raise_exception(char const * msg);
+    Z3_NORETURN void raise_exception(std::string const& msg) { raise_exception(msg.c_str()); }
+
+    std::ostream& display(std::ostream& out, parameter const& p);
 
     bool is_format_manager() const { return m_format_manager == nullptr; }
 
@@ -2569,6 +2572,16 @@ public:
     void operator()(AST * n) { m_manager.inc_ref(n); }
 };
 
+struct parameter_pp {
+    parameter const& p;
+    ast_manager& m;
+    parameter_pp(parameter const& p, ast_manager& m): p(p), m(m) {}
+};
+
+inline std::ostream& operator<<(std::ostream& out, parameter_pp const& pp) {
+    return pp.m.display(out, pp.p);
+}
+
 
 #endif /* AST_H_ */
 

src/ast/rewriter/seq_rewriter.cpp

@@ -859,10 +859,6 @@ br_status seq_rewriter::mk_seq_replace(expr* a, expr* b, expr* c, expr_ref& resu
         result = m_util.str.mk_concat(c, a);
         return BR_REWRITE1;
     }
-    if (m_util.str.is_string(a, s1) && s1.length() == 0) {
-        result = a;
-        return BR_DONE;
-    }
     return BR_FAILED;
 }