public PrinterNode Visit(CastNode node)
{
var pNode = new PrinterNode($"({node.Type.Name})");
pNode.AddChild(node.Expr.Accept(this));
return(pNode);
}
public type GetType(CastNode cnode, Environment env)
{
type t1 = TypeNodeToType(cnode.primitive, env);
type t2 = GetType(cnode.tnode, env);
bool b = t1 is NumericType && t2 is NumericType;
if (!b)
{
throw new Exception("Only numeric types can be casted");
}
return(t1);
}
public bool Visit(CastNode node)
{
if (node.Type != null)
{
return(true);
}
node.Expr.Accept(this);
if (!_typeChecker.CanCast(node.CastTo, node.Expr))
{
var t = ExprNode.GetClosestToken(node.Expr);
throw new IncompatibleTypesException(node.CastTo, node.Expr.Type, t.Lexeme, t.Line, t.Column);
}
node.Type = node.CastTo;
return(true);
}
// try cast source to target
public bool TryCast(SymType targetType, ref ExprNode source, bool canModify = true)
{
var realSourceType = source.Type is SymTypeAlias sourceTypeAlias ? sourceTypeAlias.Type : source.Type;
var realTargetType = targetType is SymTypeAlias targetTypeAlias ? targetTypeAlias.Type : targetType;
switch (realTargetType)
{
// scalars
// double
case SymDouble _:
switch (realSourceType)
{
case SymInt _:
var t = ExprNode.GetClosestToken(source);
if (!canModify)
{
return(true);
}
source = new CastNode(_stack.SymDouble, source);
source.Type = _stack.SymDouble;
return(true);
case SymDouble _:
return(true);
}
break;
// end double
// int
case SymInt _:
switch (realSourceType)
{
case SymInt _:
return(true);
}
break;
// end int
// char
case SymChar _:
switch (realSourceType)
{
case SymChar _:
return(true);
}
break;
// end char
// bool
case SymBool _:
switch (realSourceType)
{
case SymBool _:
return(true);
case SymInt _:
if (!canModify)
{
return(true);
}
source = new CastNode(_stack.SymBool, source);
source.Type = _stack.SymBool;
return(true);
}
break;
// end bool
case SymArray target:
switch (realSourceType)
{
case SymArray sourceType:
return(IsTypesEqual(target, sourceType));
}
break;
default:
return(IsTypesEqual(realSourceType, realTargetType));
}
return(false);
}
public string Print(CastNode cnode)
{
return("(" + Print(cnode.primitive) + ")" + " " + Print(cnode.tnode));
}