/// <summary>
/// Virtual
/// Check if both are Dragon.Type.Bool
/// </summary>
/// <param name="lhs"></param>
/// <param name="rhs"></param>
/// <returns>Dragon.Type.Bool or null</returns>
protected virtual Sara.Type Check(Sara.Type lhs, Sara.Type rhs)
{
if (lhs == Sara.Type.Bool && rhs == Sara.Type.Bool)
return Sara.Type.Bool;
return null;
}
/// <summary>
/// Ctor
/// </summary>
/// <param name="arr"></param>
/// <param name="idx"></param>
/// <param name="type"></param>
public Access(Id arr, Expr idx, Sara.Type type)
: base(new Word("[]", Tag.INDEX), type)
{
this.Array = arr;
this.Index = idx;
}
public Constant(Token tok, Sara.Type type)
: base(tok,type)
{ }
private Sara.Type Check(Sara.Type lhs, Sara.Type rhs)
{
if (lhs is Array || rhs is Array) return null;
else if (lhs == rhs) return rhs;
else if (Sara.Type.Numeric(lhs) && Sara.Type.Numeric(rhs)) return rhs;
else return null;
}
/// <summary>
/// Overriding
/// Check the two operands have the same type and neither is Array
/// </summary>
/// <param name="lft"></param>
/// <param name="rht"></param>
/// <returns></returns>
protected override Sara.Type Check(Sara.Type lft, Sara.Type rht)
{
if (lft is Array || rht is Array)
return null;
else
return lft == rht ? Sara.Type.Bool : null;
}
public Sara.Type Check(Sara.Type lhs, Sara.Type rhs)
{
if (Sara.Type.Numeric(lhs) && Sara.Type.Numeric(rhs))
return rhs;
else if (lhs == Sara.Type.Bool && rhs == Sara.Type.Bool)
return rhs;
else
return null;
}
public Op(Token op, Sara.Type type)
: base(op, type)
{ }
public Temp(Sara.Type type)
: base(Word.temp, type)
{
this.Number = ++Temp.Count;
}
public Id(Word id, Sara.Type type, int offset)
: base(id, type)
{
this.Offset = offset;
}
/// <summary>
///
/// </summary>
/// <param name="type"></param>
/// <returns>Type</returns>
public Sara.Type Dimension(Sara.Type type)
{
this.Match('[');
var tok = _look;
this.Match(Tag.NUM);
this.Match(']');
if (_look.TagValue == '[')
type = this.Dimension(type);
return new Array((tok as Num).Value, type);
}
