Pei He <hepeimail@gmail.com> writes:
> When I check the types of fields in a data structure, I found most
> fields are defined as general types, as List, Node. Then, To know the
> content inside the List, I need to track the usage of the fields.
> For example, the fromClause in SelectStmt is defined as List. And, the
> content in the ListCell is with the type of RangeVar.
> Is there other easier way to check the types information, rather than
> track through the code?
Usually, if a particular List field is predictably a list of just one
type of node, the declaration is (or should be) commented to tell you
that. Look at struct Query in parsenodes.h for some examples.
regards, tom lane