public override void VisitNot(ASTNot n)
{
//evaluate expression
n.Expression.Visit(this);
//compare it with 0 to negate
_gen.Emit(OpCodes.Ldc_I4_0);
_gen.Emit(OpCodes.Ceq);
_lastWalkedType = typeof(bool);
}
public override void VisitNot(ASTNot n)
{
CFlatType t = CheckSubTree(n.Expression);
if (t is TypeBool)
{
n.CFlatType = t;
_lastSeenType = t;
}
else
{
ReportError(n.Location, "Operand for the not operator must be a boolean. Got type '{0}'", TypeToFriendlyName(t));
}
}
protected override bool Visit(ASTNot node)
{
if (!Visit(node.Child))
{
return(false);
}
var childType = node.Child.TypeInfo;
if (!(childType is BooleanType))
{
Error(node.Position, $"Cannot not none Boolean type {childType}");
return(false);
}
node.TypeInfo = childType;
return(true);
}
protected override bool Visit(ASTNot node) => EmitUnary <CNot>(node);
private ASTNode ParseUnary()
{
ASTUnary topPrefix = null, leafPrefix = null;
for (;;)
{
ASTUnary res;
if (EatToken(TokenKind.ExclamationMark))
{
res = new ASTNot(EatenToken.Position);
}
else if (EatToken(TokenKind.KeywordNew))
{
res = new ASTNew(EatenToken.Position);
}
else
{
break;
}
if (topPrefix == null)
{
topPrefix = res;
leafPrefix = res;
}
else
{
leafPrefix.Child = res;
leafPrefix = res;
}
}
var result = ParseTerm();
if (result == null)
{
return(null);
}
ASTUnary topPostfix = null, leafPostfix = null;
for (;;)
{
ASTUnary res;
if (EatToken(TokenKind.SquareLeft))
{
var expr = ParseExpression();
if (expr == null)
{
return(null);
}
if (!EatExpect(TokenKind.SquareRight))
{
return(null);
}
res = new ASTIndexing(PeekToken().Position)
{
Value = expr
};
}
else if (EatToken(TokenKind.ParenthesesLeft))
{
var start = EatenToken;
var arguments = new List <ASTNode>();
while (!EatToken(TokenKind.ParenthesesRight))
{
if (arguments.Count != 0 && !EatExpect(TokenKind.Comma))
{
return(null);
}
var argument = ParseExpression();
if (argument == null)
{
return(null);
}
arguments.Add(argument);
}
res = new ASTCall(start.Position)
{
Arguments = arguments
};
}
else
{
break;
}
if (topPostfix == null)
{
leafPostfix = res;
topPostfix = res;
}
else
{
res.Child = topPostfix;
topPostfix = res;
}
}
if (leafPostfix != null)
{
leafPostfix.Child = result;
result = topPostfix;
}
if (leafPrefix != null)
{
leafPrefix.Child = result;
result = topPrefix;
}
return(result);
}
public bool Visit(ASTNot node)
{
throw new NotImplementedException();
}
protected abstract bool Visit(ASTNot node);
