private bool ImportVariable(Obj moduleName, Obj variableName, out Obj result)
{
ObjModule module = GetModule(moduleName);
if (module == null)
{
result = Obj.MakeString("Could not load module");
return(false); // Should only look up loaded modules
}
ObjString variable = variableName as ObjString;
if (variable == null)
{
result = Obj.MakeString("Variable name must be a string");
return(false);
}
int variableEntry = module.Variables.FindIndex(v => v.Name == variable.ToString());
// It's a runtime error if the imported variable does not exist.
if (variableEntry == -1)
{
result = Obj.MakeString(string.Format("Could not find a variable named '{0}' in module '{1}'.", variableName, moduleName));
return(false);
}
result = module.Variables[variableEntry].Container;
return(true);
}
internal int DefineVariable(ObjModule module, string name, Obj c)
{
if (module == null)
{
module = GetCoreModule();
}
if (module.Variables.Count == ObjModule.MaxModuleVars)
{
return(-2);
}
// See if the variable is already explicitly or implicitly declared.
int symbol = module.Variables.FindIndex(m => m.Name == name);
if (symbol == -1)
{
// Brand new variable.
module.Variables.Add(new ModuleVariable {
Name = name, Container = c
});
symbol = module.Variables.Count - 1;
}
else if (module.Variables[symbol].Container == Obj.Undefined)
{
// Explicitly declaring an implicitly declared one. Mark it as defined.
module.Variables[symbol].Container = c;
}
else
{
// Already explicitly declared.
symbol = -1;
}
return(symbol);
}
private ObjFiber LoadModule(Obj name, string source)
{
ObjModule module = GetModule(name);
// See if the module has already been loaded.
if (module == null)
{
module = new ObjModule(name as ObjString);
// Store it in the VM's module registry so we don't load the same module
// multiple times.
_modules.Set(name, module);
// Implicitly import the core module.
ObjModule coreModule = GetCoreModule();
foreach (ModuleVariable t in coreModule.Variables)
{
DefineVariable(module, t.Name, t.Container);
}
}
ObjFn fn = Compiler.Compile(this, module, name.ToString(), source, true);
if (fn == null)
{
// TODO: Should we still store the module even if it didn't compile?
return(null);
}
ObjFiber moduleFiber = new ObjFiber(fn);
// Return the fiber that executes the module.
return(moduleFiber);
}
public Obj FindVariable(string name)
{
ObjModule coreModule = GetCoreModule();
int symbol = coreModule.Variables.FindIndex(v => v.Name == name);
return(coreModule.Variables[symbol].Container);
}
public Obj FindVariable(string moduleName, string name)
{
ObjModule m = GetModuleByName(moduleName);
if (m == null)
{
return(Obj.Undefined);
}
int symbol = m.Variables.FindIndex(v => v.Name == name);
return(m.Variables[symbol].Container);
}
// Execute [source] in the context of the core module.
private InterpretResult LoadIntoCore(string source)
{
ObjModule coreModule = GetCoreModule();
ObjFn fn = Compiler.Compile(this, coreModule, "", source, true);
if (fn == null)
{
return(InterpretResult.CompileError);
}
Fiber = new ObjFiber(fn);
return(RunInterpreter() ? InterpretResult.Success : InterpretResult.RuntimeError);
}
internal int DeclareVariable(ObjModule module, string name)
{
if (module == null)
{
module = GetCoreModule();
}
if (module.Variables.Count == ObjModule.MaxModuleVars)
{
return(-2);
}
module.Variables.Add(new ModuleVariable {
Name = name, Container = Obj.Undefined
});
return(module.Variables.Count - 1);
}
public WrenVM()
{
MethodNames = new List <string>();
ObjString name = new ObjString("core");
// Implicitly create a "core" module for the built in libraries.
ObjModule coreModule = new ObjModule(name);
_modules = new ObjMap();
_modules.Set(Obj.Null, coreModule);
CoreLibrary core = new CoreLibrary(this);
core.InitializeCore();
// Load in System functions
Meta.LoadLibrary(this);
}
public WrenVM(Action <string> write, Action <string> error)
{
Write = write ?? (_ => Console.WriteLine(_));
Error = error ?? (_ => Console.Error.WriteLine(_));
MethodNames = new List <string>();
ObjString name = new ObjString("core");
// Implicitly create a "core" module for the built in libraries.
ObjModule coreModule = new ObjModule(name);
_modules = new ObjMap();
_modules.Set(Obj.Null, coreModule);
CoreLibrary core = new CoreLibrary(this);
core.InitializeCore();
// Load in System functions
Meta.LoadLibrary(this);
}
static bool Eval(WrenVM vm, Obj[] args, int stackStart)
{
if (args[stackStart + 1] is ObjString)
{
// Eval the code in the module where the calling function was defined.
Obj callingFn = vm.Fiber.GetFrame().Fn;
ObjModule module = (callingFn is ObjFn)
? ((ObjFn)callingFn).Module
: ((ObjClosure)callingFn).Function.Module;
// Compile it.
ObjFn fn = Compiler.Compile(vm, module, "", args[stackStart + 1].ToString(), false);
if (fn == null)
{
vm.Fiber.Error = Obj.MakeString("Could not compile source code.");
return(false);
}
// TODO: Include the compile errors in the runtime error message.
// Create a fiber to run the code in.
ObjFiber evalFiber = new ObjFiber(fn)
{
Caller = vm.Fiber
};
// Switch to the fiber.
args[stackStart] = evalFiber;
return(false);
}
vm.Fiber.Error = Obj.MakeString("Source code must be a string.");
return(false);
}
// Execute [source] in the context of the core module.
private IEnumerator LoadIntoCore(string source, ResultRef resultRef)
{
ObjModule coreModule = GetCoreModule();
ObjFn fn = Compiler.Compile(this, coreModule, "", source, true);
if (fn == null)
{
resultRef.value = InterpretResult.CompileError;
yield break;
}
Fiber = new ObjFiber(fn);
var succeeded = new SuccessRef();
var interpreter = RunInterpreter(succeeded);
while (interpreter.MoveNext())
{
yield return(interpreter.Current);
}
resultRef.value = succeeded.value ? InterpretResult.Success : InterpretResult.RuntimeError;
}