alternative to #24101#23892 changed the opensym experimental switch so that it has to be
enabled in the context of the generic/template declarations capturing
the symbols, not the context of the instantiation of the
generics/templates. This was to be in line with where the compiler gives
the warnings and changes behavior in a potentially breaking way.
However `results` [depends on the old
behavior](71d404b314/results.nim (L1428)),
so that the callers of the macros provided by results always take
advantage of the opensym behavior. To accomodate this, we change the
behavior of the old experimental option that `results` uses,
`genericsOpenSym`, so that ignores the information of whether or not
symbols are intentionally opened and always gives the opensym behavior
as long as it's enabled at instantiation time. This should keep
`results` working as is. However this differs from the normal opensym
switch in that it doesn't generate `nnkOpenSym`.
Before it was just a generics-only version of `openSym` along with
`templateOpenSym` which was only for templates. So `templateOpenSym` is
removed along with this change, but no one appears to have used it.
closes#1969, closes#7547, closes#7737, closes#11838, closes#12283,
closes#12714, closes#12720, closes#14053, closes#16118, closes
#19670, closes#22645
I was going to wait on these but regression tests even for recent PRs
are turning out to be important in wide reaching PRs like #24010.
The other issues with the working label felt either finnicky (#7385,
#9156, #12732, #15247), excessive to test (#12405, #12424, #17527), or I
just don't know what fixed them/what the issue was (#16128: the PR link
gives a server error by Github, #12457, #12487).
actually fixes#23865 following up #23873
In the handling of `nkIdent` in `semExpr`, the compiler looks for the
closest symbol with the name and [checks the symbol
kind](6126a0bf46/compiler/semexprs.nim (L3171))
to also consider the overloads if the symbol kind is overloadable. But
it treats the normally overloadable template/macro/module sym kinds the
same as non-overloadable symbols, just calling `semSym` on it. We need
to mirror this behavior in `semOpenSym`; we treat the captured symchoice
as a fresh identifier, so if the symbol we find is a
template/macro/module, we use that symbol immediately as opposed to
waiting for overloads.
fixes#23865
The node flag `nfOpenSym` implemented in #23091 for sym nodes is now
also implemented for open symchoices. This means the intended behavior
is still achieved when multiple overloads are in scope to be captured,
so the issue is fixed. The code for the flag is documented and moved
into a helper proc and the experimental switch is now enabled for the
compiler test suite.
refs #23091, especially post merge comments
Unsure if `experimental` and `bind` are the perfect constructs to use
but they seem to get the job done here. Symbol nodes do not get marked
`nfOpenSym` if the `bind` statement is used for their symbol, and
`nfOpenSym` nodes do not get replaced by new local symbols if the
experimental switch is not enabled in the local context (meaning it also
works with `push experimental`). However this incurs a warning as the
fact that the node is marked `nfOpenSym` means we did not `bind` it, so
we might want to do that or turn on the experimental switch if we didn't
intend to bind it.
The experimental switch name is arbitrary and could be changed.
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
fixes#22605, separated from #22744
This marks symbol captures in macro calls in generic contexts as
`nfOpenSym`, which means if there is a new symbol in the local
instantiatied body during instantiation time, this symbol replaces the
captured symbol. We have to be careful not to consider symbols outside
of the instantiation body during instantiation, because this will leak
symbols from the instantiation context scope rather than the original
declaration scope. This is done by checking if the local context owner
(maybe should be the symbol of the proc currently getting instantiated
instead? not sure how to get this) is the same as or a parent owner of
the owner of the replacement candidate symbol.
This solution is distinct from the symchoice mechanisms which we
originally assumed had to be related, if this assumption was wrong it
would explain why this solution took so long to arrive at.
