private object InvokeMethodSymbol(MethodSymbol method, List<Ast> args)
{
// create a new memory scope. this is where arguments will get defined
// we wont overwrite any memory values since they will all be local here
MemorySpaces.CreateScope();
var count = 0;
if (method.MethodDeclr.Arguments.Count != args.Count)
{
throw new InvalidSyntax(String.Format("Wrong number of arguments passed to method {0}. Got {1}, expected {2}",
method.MethodDeclr.MethodName.Token.TokenValue,
args.Count, method.MethodDeclr.Arguments.Count));
}
foreach (VarDeclrAst expectedArgument in method.MethodDeclr.Arguments)
{
var currentArgument = args[count];
var oldmemory = MemorySpaces.Current;
// if the argument is coming from somewhere else, make sure to be able to
// load the argument from its preferred space.
if (currentArgument.CallingMemory != null)
{
MemorySpaces.Current = currentArgument.CallingMemory;
}
var value = GetValue(Exec(currentArgument));
// since we were just loading values from the argument space
// switch back to the current space so we can assign the argument value
// into our local working memory
MemorySpaces.Current = oldmemory;
if (expectedArgument.VariableValue == null)
{
MemorySpaces.Current.Define(expectedArgument.Token.TokenValue, value);
}
else
{
MemorySpaces.Current.Assign(expectedArgument.Token.TokenValue, value);
}
// if the passed in argument is a word and not a literal (like string or bool) then
// pull its value from memory so we can match type to the target type
var resolvedSymbol = (currentArgument.Token.TokenType == TokenType.Word ?
MemorySpaces.Current.Get(currentArgument.Token.TokenValue)
: args[count]) as Symbol;
var resolvedType = resolvedSymbol != null ? resolvedSymbol.Type : currentArgument.AstSymbolType;
if (currentArgument is MethodDeclr)
{
resolvedType = new BuiltInType(ExpressionTypes.Method);
}
if (!TokenUtil.EqualOrPromotable(expectedArgument.AstSymbolType, resolvedType))
{
throw new InvalidSyntax(String.Format("Cannot pass argument {0} of type {1} to function {2} as argument {3} of type {4}",
currentArgument.Token.TokenValue,
currentArgument.AstSymbolType.TypeName,
method.MethodDeclr.MethodName.Token.TokenValue,
expectedArgument.VariableName.Token.TokenValue,
expectedArgument.AstSymbolType.TypeName));
}
count++;
}
var val = Exec(method.MethodDeclr.Body);
MemorySpaces.PopScope();
return val;
}
private void VariableDeclaration(VarDeclrAst varDeclrAst)
{
if (varDeclrAst.VariableValue == null)
{
var symbol = varDeclrAst.CurrentScope.Resolve(varDeclrAst.VariableName.Token.TokenValue);
var space = MemorySpaces.Current;
space.Define(symbol.Name, TokenType.Nil);
return;
}
var variableValue = varDeclrAst.VariableValue.ConvertedExpression ?? varDeclrAst.VariableValue;
// if the rhs of a variable is not a method, then execute it,
if (variableValue.AstType != AstTypes.MethodDeclr)
{
var value = GetValue(Exec(variableValue));
if (value != null)
{
var symbol = varDeclrAst.CurrentScope.Resolve(varDeclrAst.VariableName.Token.TokenValue);
var space = MemorySpaces.Current;
if (variableValue.IsLink)
{
space.Link(symbol.Name, variableValue.Token.TokenValue);
}
else
{
space.Define(symbol.Name, value);
}
}
}
else
{
var symbol = varDeclrAst.CurrentScope.Resolve(varDeclrAst.VariableName.Token.TokenValue);
var resolvedMethod = varDeclrAst.CurrentScope.Resolve(variableValue.Token.TokenValue) as MethodSymbol;
// make sure to create a NEW method symbol. this way each time we declare this item
// it will create a local copy and get its own memory space for closures.
// if we shared the same method symbol then all instances of the same declaration would share the memory space,
// which may not be what we want given class instances having their own spaces
var localMethodCopy = new MethodSymbol(resolvedMethod.Name, resolvedMethod.Type,
resolvedMethod.MethodDeclr);
var space = MemorySpaces.Current;
if (variableValue is LambdaDeclr)
{
localMethodCopy.Environment = space;
}
space.Define(symbol.Name, localMethodCopy);
}
}
private LambdaDeclr CreateCurriedMethod(FuncInvoke ast, MethodSymbol functionType)
{
var srcMethod = functionType.MethodDeclr;
var fixedAssignments = new List<VarDeclrAst>();
var count = 0;
foreach (var argValue in ast.Arguments)
{
var srcArg = srcMethod.Arguments[count] as VarDeclrAst;
var token = new Token(srcArg.DeclarationType.Token.TokenType, argValue.Token.TokenValue);
var declr = new VarDeclrAst(token, srcArg.Token, new Expr(argValue.Token));
// if we're creating a curry using a variable then we need to resolve the variable type
// otherwise we can make a symbol for the literal
var newArgType = argValue.Token.TokenType == TokenType.Word ?
ast.CurrentScope.Resolve(argValue).Type
: ScopeUtil.CreateSymbolType(argValue);
// create a symbol type for the target we're invoking on so we can do type checking
var targetArgType = ScopeUtil.CreateSymbolType(srcArg.DeclarationType);
if (!TokenUtil.EqualOrPromotable(newArgType, targetArgType))
{
throw new InvalidSyntax(String.Format("Cannot pass argument {0} of type {1} to partial function {2} as argument {3} of type {4}",
argValue.Token.TokenValue,
newArgType.TypeName,
srcMethod.MethodName.Token.TokenValue,
srcArg.VariableName.Token.TokenValue,
targetArgType.TypeName));
}
fixedAssignments.Add(declr);
count++;
}
var newBody = fixedAssignments.Concat(srcMethod.Body.ScopedStatements).ToList();
var curriedMethod = new LambdaDeclr(srcMethod.Arguments.Skip(ast.Arguments.Count).ToList(), new ScopeDeclr(newBody));
SetScope(curriedMethod);
return curriedMethod;
}