public bool VerifyExpression(SymbolTable symbolTable, Expression expression)
{
//
// Verify expression.
//
try
{
GetExpressionType(symbolTable, expression);
return true;
}
catch (VerifierException x)
{
System.Diagnostics.Debug.WriteLine(x.Message);
return false;
}
}
/// <summary>
/// Конструктор
/// </summary>
/// <param name="value"></param>
public Return(Expression value)
{
Value = value;
}
public Type GetExpressionType(SymbolTable symbolTable, Expression expression)
{
if (expression is UnaryExpression)
{
UnaryExpression unary = (UnaryExpression)expression;
return FindType(GetExpressionType(symbolTable, unary.Value), unary.UnaryOperatorType);
}
else if (expression is BinaryExpression)
{
BinaryExpression binary = (BinaryExpression)expression;
return FindType(GetExpressionType(symbolTable, binary.Left), GetExpressionType(symbolTable, binary.Right), binary.BinaryOperatorType);
}
else if (expression is Literal)
{
Literal literal = expression as Literal;
if (literal.LiteralType == LiteralType.Boolean)
return new Type(PrimitiveType.Boolean);
if (literal.LiteralType == LiteralType.Character)
return new Type(PrimitiveType.Character);
if (literal.LiteralType == LiteralType.Integer)
return new Type(PrimitiveType.Integer);
if (literal.LiteralType == LiteralType.Real)
return new Type(PrimitiveType.Real);
if (literal.LiteralType == LiteralType.String)
return new Type(PrimitiveType.Void);
}
else if (expression is Name)
{
return ((Variable)symbolTable.Find(((Name)expression).Value, SymbolType.Variable).SyntaxObject).Type;
}
else if (expression is Call)
{
return ((Call)expression).Type;
}
return null;
}
public For(Body body, Assignment counter, Expression condition, Assignment initializer)
{
Body = body; Counter = counter; Condition = condition; Initializer = initializer;
}
public If(Body elseBody, Body ifBody, Expression condition)
{
ElseBody = elseBody; IfBody = ifBody; Condition = condition;
}
public Do(Expression condition, Body body)
{
Body = body;
Condition = condition;
}
/// <summary>
/// Creates a expression element object.
/// </summary>
public Element(Expression expression)
{
ElementType = ElementType.Expression;
Expression = expression;
}
public While(Body body, Expression condition)
{
Body = body;
Condition = condition;
}
/// <summary>
/// Конструктор
/// </summary>
/// <param name="value"></param>
public Continue(Expression value)
{
Value = value;
}
public UnaryExpression(Expression indexer, Expression value, UnaryOperatorType unaryOperatorType)
{
Value = value; Indexer = indexer; UnaryOperatorType = unaryOperatorType;
}
/// <summary>
/// Конструктор
/// </summary>
/// <param name="value"></param>
public Break(Expression value)
{
Value = value;
}
public BinaryExpression(Expression right, Expression left, BinaryOperatorType binaryOperatorType)
{
Right = right; Left = left; BinaryOperatorType = binaryOperatorType;
}
public Assignment(Expression value, Expression index, string name)
{
Value = value; Name = name; Index = index;
}
/// <summary>
/// конструктор
/// </summary>
public Argument(Expression value, PassMethod passMethod)
{
Value = value; PassMethod = passMethod;
}