add global scope variables

src/script/context.cpp

@@ -106,6 +106,11 @@ ScriptValueP Context::eval(const Script& script, bool useScope) {
           setVariable((Variable)i.data, stack.back());
           break;
         }
+        // Set a global variable
+        case I_SET_GLB: {
+          setGlobalVariable((Variable)i.data, stack.back());
+          break;
+        }
 
         // Get an object member
         case I_MEMBER_C: {
@@ -270,13 +275,26 @@ void Context::setVariable(Variable name, const ScriptValueP& value) {
     assert((size_t)name < variable_names.size());
   #endif
   VariableValue& var = variables[name];
-  if (var.level < level) {
+  if (var.level < level && !var.global_scope) {
     // keep shadow copy
     Binding bind = {name, var};
     shadowed.push_back(bind);
+  }
+  if (!var.global_scope) {
+    var.global_scope = false;
   }
   var.level = level;
   var.value = value;
+}
+
+void Context::setGlobalVariable(Variable name, const ScriptValueP& value) {
+#ifdef _DEBUG
+  assert((size_t)name < variable_names.size());
+#endif
+  VariableValue& var = variables[name];
+  var.level = level;
+  var.value = value;
+  var.global_scope = true;
 }
 
 ScriptValueP Context::getVariable(const String& name) {

src/script/context.hpp

@@ -53,7 +53,8 @@ class Context {
   /// Set a variable to a new value (in the current scope)
   void setVariable(const String& name, const ScriptValueP& value);
   /// Set a variable to a new value (in the current scope)
-  void setVariable(Variable name, const ScriptValueP& value);
+  void setVariable(Variable name, const ScriptValueP& value);
+  void setGlobalVariable(Variable name, const ScriptValueP& value);
 
   /// Get the value of a variable, throws if it not set
   ScriptValueP getVariable(const String& name);
@@ -88,7 +89,8 @@ class Context {
   struct VariableValue {
     VariableValue() : level(0) {}
     unsigned int level; ///< Scope level on which this variable was set
-    ScriptValueP value; ///< Value of this variable
+    ScriptValueP value; ///< Value of this variable
+    bool global_scope = false; ///< Is this variable globally scoped? 
   };
   /// Record of a variable binding that is being shadowed (overwritten) by another binding
   struct Binding {

src/script/dependency.cpp

@@ -301,6 +301,11 @@ ScriptValueP Context::dependencies(const Dependency& dep, const Script& script)
           setVariable((Variable)i.data, stack.back());
           break;
         }
+        // Set a global variable (as normal)
+        case I_SET_GLB: {
+          setGlobalVariable((Variable)i.data, stack.back());
+          break;
+        }
 
         // Simple instruction: unary
         case I_UNARY: {

src/script/parser.cpp

@@ -122,7 +122,7 @@ bool isOper  (wxUniChar c) { return wxStrchr(_("+-*/!.@%^&:=<>;,"),c) != nullptr
 bool isLparen(wxUniChar c) { return c==_('(') || c==_('[') || c==_('{'); }
 bool isRparen(wxUniChar c) { return c==_(')') || c==_(']') || c==_('}'); }
 bool isDigitOrDot(wxUniChar c) { return isDigit(c) || c==_('.'); }
-bool isLongOper(StringView s) { return s==_(":=") || s==_("==") || s==_("!=") || s==_("<=") || s==_(">="); }
+bool isLongOper(StringView s) { return s==_(":=") || s==_("==") || s==_("!=") || s==_("<=") || s==_(">=") || s==_("->"); }
 
 // moveme
 // ----------------------------------------------------------------------------- : Tokenizing
@@ -351,7 +351,7 @@ enum Precedence
 {  PREC_ALL
 ,  PREC_NEWLINE  // newline ;
 ,  PREC_SEQ    // ;
-,  PREC_SET    // :=
+,  PREC_SET    // := ->
 ,  PREC_AND    // and or
 ,  PREC_CMP    // == != < > <= >=
 ,  PREC_ADD    // + -
@@ -736,7 +736,7 @@ ExprType parseOper(TokenIterator& input, Script& script, Precedence minPrec, Ins
       }
       script.addInstruction(I_POP); // discard result of first expression
       type = parseOper(input, script, PREC_SET);
-    } else if (minPrec <= PREC_SET && token==_(":=")) {
+    } else if (minPrec <= PREC_SET && (token==_(":=") || token==_("->"))) {
       // We made a mistake, the part before the := should be a variable name,
       // not an expression. Remove that instruction.
       Instruction& instr = script.getInstructions().back();
@@ -745,7 +745,11 @@ ExprType parseOper(TokenIterator& input, Script& script, Precedence minPrec, Ins
         return EXPR_FAILED;
       }
       script.getInstructions().pop_back();
-      type = parseOper(input, script, PREC_SET,  I_SET_VAR, instr.data);
+      if(token==_("->")) {	  
+        type = parseOper(input, script, PREC_SET,  I_SET_GLB, instr.data);
+      } else {
+        type = parseOper(input, script, PREC_SET,  I_SET_VAR, instr.data);
+      }
       if (type == EXPR_STATEMENT) {
         input.add_error(_("Warning: the right hand side of an assignment should always yield a value."));
       }

src/script/script.cpp

@@ -176,6 +176,7 @@ String Script::dumpInstr(unsigned int pos, Instruction i) const {
     case I_JUMP_SC_OR:  ret += _("jump sc or");  break;
     case I_GET_VAR:    ret += _("get");    break;
     case I_SET_VAR:    ret += _("set");    break;
+    case I_SET_GLB:    ret += _("set_global");    break;
     case I_MEMBER_C:  ret += _("member_c");  break;
     case I_LOOP:    ret += _("loop");    break;
     case I_LOOP_WITH_KEY:ret += _("loop with key"); break;
@@ -236,7 +237,7 @@ String Script::dumpInstr(unsigned int pos, Instruction i) const {
     case I_CALL: case I_CLOSURE: case I_DUP:  // int
       ret += String::Format(_("\t%d"), i.data);
       break;
-    case I_GET_VAR: case I_SET_VAR: case I_NOP:          // variable
+    case I_GET_VAR: case I_SET_VAR: case I_NOP: case I_SET_GLB:          // variable
       ret += _("\t") + variable_to_string((Variable)i.data);
       break;
   }

src/script/script.hpp

@@ -30,6 +30,7 @@ enum InstructionType
   // Variables
 ,  I_GET_VAR       = 4  ///< arg = var        : find a variable, push its value onto the stack, it is an error if the variable is not found
 ,  I_SET_VAR       = 5  ///< arg = var        : assign the top value from the stack to a variable (doesn't pop)
+,  I_SET_GLB       = 21 ///< arg = var        : assign the top value from the stack to a global variable (doesn't pop)
   // Objects
 ,  I_MEMBER_C      = 6  ///< arg = const name : finds a member of the top of the stack replaces the top of the stack with the member
 ,  I_LOOP          = 7  ///< arg = address    : loop over the elements of an iterator, which is the *second* element of the stack (this allows for combing the results of multiple iterations)