protected final function IsExpressionConstant(CoreExpression $Expression)
{
switch (true) {
case $Expression instanceof ConstantExpression:
return true;
case $Expression instanceof ColumnExpression:
return false;
case $Expression instanceof UnaryOperationExpression:
return $this->IsExpressionConstant($Expression->GetOperandExpression());
case $Expression instanceof BinaryOperationExpression:
return $this->IsExpressionConstant($Expression->GetLeftOperandExpression()) && $this->IsExpressionConstant($Expression->GetRightOperandExpression());
case $Expression instanceof CompoundBooleanExpression:
return $this->AreExpressionsConstant($Expression->GetBooleanExpressions());
case $Expression instanceof FunctionCallExpression:
return $this->AreExpressionsConstant($Expression->GetArgumentValueListExpression()->GetValueExpressions());
default:
return false;
}
}
