Re: Using Expanded Objects other than Arrays from plpgsql

I wrote:
> Hmm, it seemed to still apply for me. But anyway, I needed to make
> the other changes, so here's v4.

I decided to see what would happen if we tried to avoid the code
duplication in pl_funcs.c by making some "walker" infrastructure
akin to expression_tree_walker. While that doesn't seem useful
for the dump_xxx functions, it works very nicely for the free_xxx
functions and now for the mark_xxx ones as well. pl_funcs.c
nets out about 400 lines shorter than in the v4 patch. The
code coverage score for the file is still awful :-(, but that's
because we're not testing the dump_xxx functions at all.

PFA v5. The new 0001 patch refactors the free_xxx infrastructure
to create plpgsql_statement_tree_walker(), and then in what's now
0003 we can use that instead of writing a lot of duplicate code.

regards, tom lane