xo-interpreter: plumb initial global symtab so builtins reach parser

examples/exprrepl/exprrepl.cpp

@@ -46,10 +46,11 @@ main() {
     using span_type = xo::scm::span<const char>;
 
     bool interactive = isatty(STDIN_FILENO);
-
     bool c_debug_flag = false;
 
-    reader rdr(c_debug_flag);
+    auto toplevel_symtab = GlobalSymtab::make_empty();
+
+    reader rdr(toplevel_symtab, c_debug_flag);
     rdr.begin_interactive_session();
 
     string input_str;

examples/exprreplxx/exprreplxx.cpp

@@ -83,7 +83,9 @@ main()
 
     constexpr bool c_debug_flag = false;
 
-    reader rdr(c_debug_flag);
+    rp<GlobalSymtab> toplevel_symtab = GlobalSymtab::make_empty();
+
+    reader rdr(toplevel_symtab, c_debug_flag);
     rdr.begin_interactive_session();
 
     string input_str;

include/xo/reader/parser.hpp

@@ -9,6 +9,7 @@
 #include "envframestack.hpp"
 #include "parser_result.hpp"
 #include "parserstatemachine.hpp"
+#include "xo/expression/GlobalSymtab.hpp"
 #include <stdexcept>
 
 namespace xo {
@@ -161,9 +162,12 @@ namespace xo {
             /** create parser in initial state;
              *  parser is ready to receive tokens via @ref include_token
              *
+             *  At least for xo-interpreter will have non-empty symbol table.
+             *
+             *  @p toplevel_symtab  symbol table.
              *  @p debug_flag  true to enable debug logging
              **/
-            explicit parser(bool debug_flag);
+            parser(const rp<GlobalSymtab> & toplevel_symtab, bool debug_flag);
 
             bool debug_flag() const { return psm_.debug_flag(); }
 

include/xo/reader/reader.hpp

@@ -8,6 +8,7 @@
 #include "parser.hpp"
 #include "reader_error.hpp"
 #include "xo/expression/Expression.hpp"
+#include "xo/expression/GlobalSymtab.hpp"
 #include "xo/expression/pretty_expression.hpp"
 #include "xo/tokenizer/tokenizer.hpp"
 
@@ -78,7 +79,7 @@ namespace xo {
             using span_type = tokenizer_type::span_type;
 
         public:
-            explicit reader(bool debug_flag);
+            reader(const rp<GlobalSymtab> & toplevel_symtab, bool debug_flag);
 
             bool debug_flag() const { return parser_.debug_flag(); }
 

src/reader/parser.cpp

@@ -24,13 +24,15 @@ namespace xo {
     namespace scm {
         // ----- parser -----
 
-        parser::parser(bool debug_flag)
+        parser::parser(const rp<GlobalSymtab> & toplevel_symtab, bool debug_flag)
             : psm_{debug_flag}
         {
+#ifdef OBSOLETE
             /* top-level environment.  initially empty */
             rp<SymbolTable> toplevel_env = GlobalSymtab::make_empty();
+#endif
 
-            this->psm_.env_stack_.push_envframe(toplevel_env);
+            this->psm_.env_stack_.push_envframe(toplevel_symtab);
         }
 
         bool

src/reader/reader.cpp

@@ -4,9 +4,9 @@
 
 namespace xo {
     namespace scm {
-        reader::reader(bool debug_flag) :
+        reader::reader(const rp<GlobalSymtab> & toplevel_symtab, bool debug_flag) :
             tokenizer_{debug_flag},
-            parser_{debug_flag}
+            parser_{toplevel_symtab, debug_flag}
         {}
 
         void

utest/parser.test.cpp

@@ -10,6 +10,7 @@
 namespace xo {
     using parser_type = xo::scm::parser;
     using token_type = parser_type::token_type;
+    using xo::scm::GlobalSymtab;
     using xo::scm::exprstatetype;
     using xo::scm::define_xs;
     using xo::scm::defexprstatetype;
@@ -23,7 +24,9 @@ namespace xo {
             for (std::size_t i_tc = 0; i_tc < 2; ++i_tc) {
                 constexpr bool c_debug_flag = true;
 
-                parser_type parser(c_debug_flag);
+                rp<GlobalSymtab> toplevel_symtab = GlobalSymtab::make_empty();
+
+                parser_type parser(toplevel_symtab, c_debug_flag);
 
                 scope log(XO_DEBUG(c_debug_flag), xtag("i_tc", i_tc));
 

utest/reader.test.cpp

@@ -5,6 +5,7 @@
 
 namespace xo {
     using xo::scm::reader;
+    using xo::scm::GlobalSymtab;
 
     namespace ut {
         namespace {
@@ -30,7 +31,9 @@ namespace xo {
             for (std::size_t i_tc = 0; i_tc < s_testcase_v.size(); ++i_tc) {
                 const test_case & tc = s_testcase_v[i_tc];
 
-                reader rdr(c_debug_flag);
+                rp<GlobalSymtab> toplevel_symtab = GlobalSymtab::make_empty();
+
+                reader rdr(toplevel_symtab, c_debug_flag);
 
                 scope log(XO_ENTER2(always, c_debug_flag, "reader.testcase"),
                            xtag("i_tc", i_tc));