public static Expression[] VisitBlockExpressions(ExpressionVisitor visitor, BlockExpression block)
{
Expression[] newNodes = null;
for (int i = 0, n = block.ExpressionCount; i < n; i++)
{
Expression curNode = block.GetExpression(i);
Expression node = visitor.Visit(curNode);
if (newNodes != null)
{
newNodes[i] = node;
}
else if (!object.ReferenceEquals(node, curNode))
{
newNodes = new Expression[n];
for (int j = 0; j < i; j++)
{
newNodes[j] = block.GetExpression(j);
}
newNodes[i] = node;
}
}
return newNodes;
}