refs #24010, refs
https://github.com/nim-lang/Nim/issues/24125#issuecomment-2358377076
The generic mismatch errors added in #24010 made it possible for `nArg`
to be `nil` in the error reporting since it checked the call argument
list, not the generic parameter list for the mismatching argument node,
which causes a segfault. This is fixed by checking the generic parameter
list immediately on any generic mismatch error.
Also the `typedesc` type is skipped for the value of the generic params
since it's redundant and the generic parameter constraints don't have
it.
fixes#24099
If an arbitrary expression without a proc type (in this case
`tyFromExpr`) is called, the compiler [passes it to overload
resolution](793cee4de1/compiler/semexprs.nim (L1223)).
But overload resolution also can't handle arbitrary expressions and
treats them as not participating at all, matching with the state
`csEmpty`. The compiler checks for this and gives an "identifier
expected" error. Instead, now if we are in a generic context and an
arbitrary expression call matched with `csEmpty`, we now return
`csNoMatch` so that `semResolvedCall` can leave it untyped as
appropriate.
The expression flag `efNoDiagnostics` is replaced with this check. It's
not checked anywhere else and the only place that uses it is
`handleCaseStmtMacro`. Replacing it with `efNoUndeclared`, we just get
`csEmpty` instead of `csNoMatch`, which is handled the same way here. So
`efNoDiagnostics` is now removed and `efNoUndeclared` is used instead.
fixes#23397
All ambiguous symbols generate symchoices for call arguments since
#23123. So, if a type mismatch receives a symchoice node for an
argument, we now treat it as an ambiguous identifier and list the
ambiguous symbols in the error message.
The magic `mArrGet`/`mArrPut` subscript overloads always match, so if a
subscript doesn't match any other subscript overloads and isn't a
regular language-handled subscript, it creates a fake overload mismatch
error in `semArrGet` that doesn't have any information (gives stuff like
"first mismatch at index: 0" for every single mismatch). Instead of
generating the fake mismatches, we only generate the fake mismatch for
`mArrGet`/`mArrPut`, and process every overload except them as a real
call and get the errors from there.
fixes#16376
The way the compiler handled generic proc instantiations in calls (like
`foo[int](...)`) up to this point was to instantiate `foo[int]`, create
a symbol for the instantiated proc (or a symchoice for multiple procs
excluding ones with mismatching generic param counts), then perform
overload resolution on this symbol/symchoice. The exception to this was
when the called symbol was already a symchoice node, in which case it
wasn't instantiated and overloading was called directly ([these
lines](b7b1313d21/compiler/semexprs.nim (L3366-L3371))).
This has several problems:
* Templates and macros can't create instantiated symbols, so they
couldn't participate in overloaded explicit generic instantiations,
causing the issue #16376.
* Every single proc that can be instantiated with the given generic
params is fully instantiated including the body. #9997 is about this but
isn't fixed here since the instantiation isn't in a call.
The way overload resolution handles explicit instantiations by itself is
also buggy:
* It doesn't check constraints.
* It allows only partially providing the generic parameters, which makes
sense for implicit generics, but can cause ambiguity in overloading.
Here is how this PR deals with these problems:
* Overload resolution now always handles explicit generic instantiations
in calls, in `initCandidate`, as long as the symbol resolves to a
routine symbol.
* Overload resolution now checks the generic params for constraints and
correct parameter count (ignoring implicit params). If these don't
match, the entire overload is considered as not matching and not
instantiated.
* Special error messages are added for mismatching/missing/extra generic
params. This is almost all of the diff in `semcall`.
* Procs with matching generic parameters now instantiate only the type
of the signature in overload resolution, not the proc itself, which also
works for templates and macros.
Unfortunately we can't entirely remove instantiations because overload
resolution can't handle some cases with uninstantiated types even though
it's resolved in the binding (see the last 2 blocks in
`texplicitgenerics`). There are also some instantiation issues with
default params that #24005 didn't fix but I didn't want this to become
the 3rd huge generics PR in a row so I didn't dive too deep into trying
to fix them. There is still a minor instantiation fix in `semtypinst`
though for subscripts in calls.
Additional changes:
* Overloading of `[]` wasn't documented properly, it somewhat is now
because we need to mention the limitation that it can't be done for
generic procs/types.
* Tests can now enable the new type mismatch errors with just
`-d:testsConciseTypeMismatch` in the command.
Package PRs:
- using fork for now:
[combparser](https://github.com/PMunch/combparser/pull/7) (partial
generic instantiation)
- merged: [cligen](https://github.com/c-blake/cligen/pull/233) (partial
generic instantiation but non-overloaded + template)
- merged: [neo](https://github.com/andreaferretti/neo/pull/56) (trying
to instantiate template with no generic param)
updated version of #22193
After #22029 and the followups #23983 and #24005 which fixed issues with
it, `tyFromExpr` no longer match any proc params in generic type bodies
but delay all non-matching calls until the type is instantiated.
Previously the mechanism `fauxMatch` was used to pretend that any
failing match against `tyFromExpr` actually matched, but prevented the
instantiation of the type until later.
Since this mechanism is not needed anymore for `tyFromExpr`, it is now
only used for `tyError` to prevent cascading errors and changed to a
bool field for simplicity. A change in `semtypes` was also needed to
prevent calling `fitNode` on default param values resolving to type
`tyFromExpr` in generic procs for params with non-generic types, as this
would try to coerce the expression into a concrete type when it can't be
instantiated yet.
The aliases `tyProxy` and `tyUnknown` for `tyError` and `tyFromExpr` are
also removed for uniformity.
fixes#21258
When a generic proc is instantiated, if one of the default values
doesn't match the type of the parameter, `seminst` sets the default
parameter node to an `nkEmpty` node with `tyError` type. `sigmatch`
checks for this to give an error message if the default param is
actually used, but only while actively matching the proc signature,
before the proc is even instantiated. The error message also gives very
little information.
Now, we check for this in `updateDefaultParams` at the end of
`semResolvedCall`, after the proc has been instantiated. The `nkEmpty`
node also is given the original mismatching type instead rather than
`tyError`, only setting `tyError` after erroring to prevent cascading
errors. The error message is changed to the standard type mismatch error
also giving the instantiation info of the routine.
fixes#19737
As in the diff, `semResolvedCall` sets the return type of a call to a
proc to the type of the call. But in the case of the [subscript
magic](https://nim-lang.org/docs/system.html#%5B%5D%2CT%2CI), this type
is the first generic param which is also supposed to be the type of the
first argument, but this is invalid, the correct type is the element
type eventually given by `semSubscript`. Some lines above also [prevent
the subscript magics from instantiating their
params](dda638c1ba/compiler/semcall.nim (L699))
so this type ends up being an unresolved generic param.
Since the type of the node is not `nil`, `prepareOperand` doesn't try to
type it again, and this unresolved generic param type ends up being the
final type of the node. To prevent this, we just never set the type of
the node if we encountered a subscript magic.
Maybe we could also rename the generic parameters of the subscript
magics to stuff like `DummyT`, `DummyI` if we want this to be easier to
debug in the future.
fixes#23406, closes#23854, closes#23855 (test code of both compiles
but separate issue exists), refs #23432, follows #23411
In generic bodies, previously all regular `nkCall` nodes like `foo(a,
b)` were directly treated as generic statements and delayed immediately,
but other call kinds like `a.foo(b)`, `foo a, b` etc underwent
typechecking before making sure they have to be delayed, as implemented
in #22029. Since the behavior for `nkCall` was slightly buggy (as in
#23406), the behavior for all call kinds is now to call `semTypeExpr`.
However the vast majority of calls in generic bodies out there are
`nkCall`, and while there isn't a difference in the expected behavior,
this exposes many issues with the implementation started in #22029 given
how much more code uses it now. The portion of these issues that CI has
caught are fixed in this PR but it's possible there are more.
1. Deref expressions, dot expressions and calls to dot expressions now
handle and propagate `tyFromExpr`. This is most of the changes in
`semexprs`.
2. For deref expressions to work in `typeof`, a new type flag
`tfNonConstExpr` is added for `tyFromExpr` that calls `semExprWithType`
with `efInTypeof` on the expression instead of `semConstExpr`. This type
flag is set for every `tyFromExpr` type of a node that `prepareNode`
encounters, so that the node itself isn't evaluated at compile time when
just trying to get the type of the node.
3. Unresolved `static` types matching `static` parameters is now treated
the same as unresolved generic types matching `typedesc` parameters in
generic type bodies, it causes a failed match which delays the call
instantiation.
4. `typedesc` parameters now reject all types containing unresolved
generic types like `seq[T]`, not just generic param types by themselves.
(using `containsGenericType`)
5. `semgnrc` now doesn't leave generic param symbols it encounters in
generic type contexts as just identifiers, and instead turns them into
symbol nodes. Normally in generic procs, this isn't a problem since the
generic param symbols will be provided again at instantiation time (and
in fact creating symbol nodes causes issues since `seminst` doesn't
actually instantiate proc body node types).
But generic types can try to be instantiated early in `sigmatch` which
will give an undeclared identifier error when the param is not provided.
Nodes in generic types (specifically in `tyFromExpr` which should be the
only use for `semGenericStmt`) undergo full generic type instantiation
with `prepareNode`, so there is no issue of these symbols remaining as
uninstantiated generic types.
6. `prepareNode` now has more logic for which nodes to avoid
instantiating.
Subscripts and subscripts turned into calls to `[]` by `semgnrc` need to
avoid instantiating the first operand, since it may be a generic body
type like `Generic` in an expression like `Generic[int]`.
Dot expressions cannot instantiate their RHS as it may be a generic proc
symbol or even an undeclared identifier for generic param fields, but
have to instantiate their LHS, so calls and subscripts need to still
instantiate their first node if it's a dot expression.
This logic still isn't perfect and needs the same level of detail as in
`semexprs` for which nodes can be left as "untyped" for overloading/dot
exprs/subscripts to handle, but should handle the majority of cases.
Also the `efDetermineType` requirement for which calls become
`tyFromExpr` is removed and as a result `efDetermineType` is entirely
unused again.
The following would crash nimsuggest on init:
```nim
import chronos
type
HistoryQuery = object
start: int
limit: int
HistoryResult = object
messages: string
type HistoryQueryHandler* = proc(req: HistoryQuery): Future[HistoryResult] {.async, gcsafe.}
```
* fix generic param substitution in templates
fixes#13527, fixes#17240, fixes#6340, fixes#20033, fixes#19576, fixes#19076
* fix bare except in test, test updated packages in CI
* Play with typeRel
* Temp solution: Fixup call's param types
* Test result type with two generic params
* Asserts
* Tiny cleanup
* Skip sink
* Ignore proc
* Use changeType
* Remove conversion
* Remove last bits of conversion
* Flag
---------
Co-authored-by: SirOlaf <>
* Infer generic bindings
* Simple test
* Add t
* Allow it to work for templates too
* Fix some builds by putting bindings in a template
* Fix builtins
* Slightly more exotic seq test
* Test value-based generics using array
* Pass expectedType into buildBindings
* Put buildBindings into a proc
* Manual entry
* Remove leftover `
* Improve language used in the manual
* Experimental flag and fix basic constructors
* Tiny commend cleanup
* Move to experimental manual
* Use 'kind' so tuples continue to fail like before
* Explicitly disallow tuples
* Table test and document tuples
* Test type reduction
* Disable inferGenericTypes check for CI tests
* Remove tuple info in manual
* Always reduce types. Testing CI
* Fixes
* Ignore tyGenericInst
* Prevent binding already bound generic params
* tyUncheckedArray
* Few more types
* Update manual and check for flag again
* Update tests/generics/treturn_inference.nim
* var candidate, remove flag check again for CI
* Enable check once more
---------
Co-authored-by: SirOlaf <>
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
* sacrifice "tgenericshardcases" for working statics
* legacy switch for CI, maybe experimental later
* convert to experimental
* apparently untyped needs the experimental switch
* try special case call semcheck
* try fix
* fix compilation
* final cleanup, not experimental, make `when` work
* remove last needed use of untyped
* fix unused warning in test
* remove untyped feature
* Make pickBestCandidate store syms
* Remove useless cursor
* Try making pickBestCandidate more readable
* Fix advance order
* Revert back to seq with lots of comments
---------
Co-authored-by: SirOlaf <>
* better error messages for dot operators [backport]
fixes#13063
* also fixes#7777
* fix#6981 and #9831 too
* fix
* minor improvement
* sus test fixes
* make test multiplatform lol
* fix nimsuggest test, extra improvements
* fix semcase on tySequence and tyObject #20283#19682
* use better arg name
* avoiding returns nil use errorNode instead, clean code
* use efNoDiagnostics flag
* remove tests/errmsgs/t19682.nim
* combine 2 test cases to one file
* .forbids pragma: defining illegal effects for proc types
This patch intends to define the opposite of the .tags pragma: a way to define effects which are not allowed in a proc.
* updated documentation and changelogs for the forbids pragma
* renamed notTagEffects to forbiddenEffects
* corrected issues of forbids pragma
the forbids pragma didn't handle simple restrictions properly and it also had issues with subtyping
* removed incorrect character from changelog
* added test to cover the interaction of methods and the forbids pragma
* covering the interaction of the tags and forbids pragmas
* updated manual about the forbids pragma
* removed useless statement
* corrected the subtyping of proc types using the forbids pragma
* updated manual for the forbids pragma
* updated documentations for forbids pragma
* updated nim docs
* updated docs with rsttester.nim
* regenerated documentation
* updated rst docs
* Update changelog.md
Co-authored-by: ringabout <43030857+ringabout@users.noreply.github.com>
* updated changelog
* corrected typo
Co-authored-by: ringabout <43030857+ringabout@users.noreply.github.com>
* fixes#17369
* megatest is green for --cpu:arm64
* docgen output includes more tags/raises
* implemented 'effectsOf'
* algorithm.nim: uses new effectsOf annotation
* closes#18376
* closes#17475
* closes#13905
* allow effectsOf: [a, b]
* added a test case
* parameters that are not ours cannot be declared as .effectsOf
* documentation
* manual: added the 'sort' example
* bootstrap with the new better options
* Added more concise calling convention/pragma mismatch messages
* Now only adds callConvMsg/lock message when sensible
* Fixed message formatting
* Added tests, and fixed some bugs
* Tests joined, and always indenting
* More tests and more bug fixes
* Fixed first test in tprocmismatch
* Using var param for writting mismatches
* Better logic for handling proc type rel and conv/pragma mismatch
* Refactored getProcConvMismatch
* Fixed callConv message formatting
* Fixed test for proper message
* Cleanup to address issues
* getProcConvMismatch now returns tuple, and reformatted code
* fix failing test toSeq in manual which now works
* changelog
* reject proc fn(a: iterable)
* add iterable to spec
* remove MCS/UFCS limitation that now works
* simplified proc-like name ident to symbol code
* wip - reworking generic param sem
* wip - closer to removing nkEmpty generic params
* it's hacky but tests pass
* slowly tweaking semProcAux to take on semLambda
* fix pragma superset check proto vs current
* Set the symbol owner earlier
* partial progress reworking proto
found bug where default values between forward and impl lead to overload
resolution issues.
* simplified pragma handling and callConv checks
Co-authored-by: Clyybber <Clyybber@users.noreply.github.com>
* partially working
* cgexprs issue
* It works!
* comment clean-up
* clean-up asserts, comments, and other bits
* add isGenericParams, inline isGeneric queries
* seeing if this is sufficiently consistent
* can use this approach or continue it in a further PR
* commentary about nullary generics and clean-ups
* fixed a mistake in PNode isGenericRoutine
* Some small cleanups
* Small cleanup
* for func lambdas ensure we use lambda pragmas
* add some basic compileTime func tests
* [ci skip] remove comments
Co-authored-by: Clyybber <Clyybber@users.noreply.github.com>
Co-authored-by: Clyybber <darkmine956@gmail.com>
