INode MakeSubstring(FunctionCall substringCall)
{
if (substringCall == null)
{
throw new ArgumentNullException("substringCall");
}
substringCall.Name = TailorUtil.GetCapitalized(TailorUtil.MID);
ExpressionItem val = substringCall.ExpressionArguments;
if (val == null)
{
throw new InvalidOperationException("No parameters for SUBSTRING.");
}
ExpressionItem start = val.Next;
if (start == null)
{
throw new InvalidOperationException("Too few parameters for SUBSTRING.");
}
ExpressionItem len = start.Next;
INode cond = MakeNotNullCheck(start); // Mid actually handles NULL
// in the first parameter
if (len == null)
{
// We don't need to add length in the normal case, but it's
// useful when the start position is too large and the call
// ought to fail (which Mid doesn't, unless it's called with
// a negative length).
IExpression argument = TailorUtil.MakeLenArg(start.Expression,
val.Expression, "Len");
start.Add(new ExpressionItem(argument));
}
else
{
if (len.Next != null)
{
throw new InvalidOperationException("Too many parameters for SUBSTRING.");
}
}
if (cond == null)
{
return(substringCall);
}
else
{
FunctionCall iifCall = new FunctionCall("Iif");
iifCall.ExpressionArguments = new ExpressionItem(cond);
iifCall.ExpressionArguments.Add(new ExpressionItem(NullValue.Value));
iifCall.ExpressionArguments.Add(new ExpressionItem(substringCall));
return(iifCall);
}
}
INode MakeSubstring(FunctionCall substringCall)
{
if (substringCall == null)
{
throw new ArgumentNullException("substringCall");
}
if (TailorUtil.HasNullArgument(substringCall))
{
return(NullValue.Value);
}
ExpressionItem val = substringCall.ExpressionArguments;
if (val == null)
{
throw new InvalidOperationException("No parameters for SUBSTRING.");
}
ExpressionItem start = val.Next;
if (start == null)
{
throw new InvalidOperationException("Too few parameters for SUBSTRING.");
}
ExpressionItem len = start.Next;
// before adding len to the list
Expression when = MakeNotNullCheck(substringCall.ExpressionArguments);
if (len == null)
{
IExpression argument = TailorUtil.MakeLenArg(start.Expression,
val.Expression, "LEN");
start.Add(new ExpressionItem(argument));
}
else
{
if (len.Next != null)
{
throw new InvalidOperationException("Too many parameters for SUBSTRING.");
}
}
if (when != null)
{
CaseExpression caseExpression = new CaseExpression();
caseExpression.Alternatives = new CaseAlternative(when, substringCall);
Expression elseExpr = new Expression();
elseExpr.Left = NullValue.Value;
caseExpression.Else = elseExpr;
return(caseExpression);
}
else
{
return(substringCall);
}
}
