[Tolk] Embedded stdlib.tolk, CompilerState, strict includes

Several related changes:
- stdlib.tolk is embedded into a distribution (deb package or tolk-js),
  the user won't have to download it and store as a project file;
  it's an important step to maintain correct language versioning
- stdlib.tolk is auto-included, that's why all its functions are
  available out of the box
- strict includes: you can't use symbol `f` from another file
  unless you've #include'd this file
- drop all C++ global variables holding compilation state,
  merge them into a single struct CompilerState located at
  compiler-state.h; for instance, stdlib filename is also there

tolk/symtable.h

@@ -15,20 +15,15 @@
     along with TON Blockchain Library.  If not, see <http://www.gnu.org/licenses/>.
 */
 #pragma once
+
 #include "src-file.h"
 #include <functional>
 #include <memory>
-#include <vector>
 
 namespace tolk {
 
-/*
- *
- *   SYMBOL VALUES (DECLARED)
- *
- */
-
 typedef int var_idx_t;
+typedef int sym_idx_t;
 
 enum class SymValKind { _Param, _Var, _Func, _Typename, _GlobVar, _Const };
 
@@ -40,11 +35,6 @@ struct SymValBase {
   virtual ~SymValBase() = default;
 };
 
-/*
- *
- *   SYMBOL TABLE
- *
- */
 
 enum class SymbolSubclass {
   undef = 0,
@@ -52,8 +42,6 @@ enum class SymbolSubclass {
   tilde_identifier = 2   // begins with ~ (a non-const method)
 };
 
-typedef int sym_idx_t;
-
 struct Symbol {
   std::string str;
   sym_idx_t idx;
@@ -73,9 +61,6 @@ private:
   std::unique_ptr<Symbol> sym[SIZE_PRIME + 1];
   sym_idx_t gen_lookup(std::string_view str, int mode = 0, sym_idx_t idx = 0);
 
-  static constexpr int max_kw_idx = 10000;
-  sym_idx_t keywords[max_kw_idx];
-
 public:
 
   static constexpr sym_idx_t not_found = 0;
@@ -88,22 +73,12 @@ public:
   Symbol* operator[](sym_idx_t i) const {
     return sym[i].get();
   }
-  bool is_keyword(sym_idx_t i) const {
-    return sym[i] && sym[i]->idx < 0;
-  }
   std::string get_name(sym_idx_t i) const {
     return sym[i] ? sym[i]->str : Symbol::unknown_symbol_name(i);
   }
   SymbolSubclass get_subclass(sym_idx_t i) const {
     return sym[i] ? sym[i]->subclass : SymbolSubclass::undef;
   }
-  Symbol* get_keyword(int i) const {
-    return ((unsigned)i < (unsigned)max_kw_idx) ? sym[keywords[i]].get() : nullptr;
-  }
-
-  SymTable() {
-    std::memset(keywords, 0, sizeof(keywords));
-  }
 };
 
 struct SymTableOverflow {
@@ -112,15 +87,6 @@ struct SymTableOverflow {
   }
 };
 
-struct SymTableKwRedef {
-  std::string kw;
-  SymTableKwRedef(std::string _kw) : kw(_kw) {
-  }
-};
-
-extern SymTable symbols;
-
-extern int scope_level;
 
 struct SymDef {
   int level;
@@ -133,18 +99,9 @@ struct SymDef {
   SymDef(int lvl, sym_idx_t idx, SrcLocation _loc, SymValBase* val = nullptr)
       : level(lvl), sym_idx(idx), value(val), loc(_loc) {
   }
-  bool has_name() const {
-    return sym_idx;
-  }
-  std::string name() const {
-    return symbols.get_name(sym_idx);
-  }
+  std::string name() const;
 };
 
-extern SymDef* sym_def[symbols.SIZE_PRIME + 1];
-extern SymDef* global_sym_def[symbols.SIZE_PRIME + 1];
-extern std::vector<std::pair<int, SymDef>> symbol_stack;
-extern std::vector<SrcLocation> scope_opened_at;
 
 void open_scope(SrcLocation loc);
 void close_scope(SrcLocation loc);