Because `prevFields` and `currentFields` have been already quoted by
`'`, no need to add another.
The error message was
```
The fields ''x'' and ''y'' cannot be initialized together, because they are from conflicting branches in the case object.
```
fixes#25117
errors on `requiresInit` of `result` if it is used before
initialization. Otherwise
```nim
# prevent superfluous warnings about the same variable:
a.init.add s.id
```
It produces a warning, and this line prevents it from being recognized
by the `requiresInit` check in `trackProc`
A function with an illegal parameter name like
```nim
proc myproc(type: int) =
echo type
```
would uninformatively fail like so:
```nim
tkeywordparam.nim(1, 13) Error: expected closing ')'
```
This commit makes it return the following error:
```nim
tkeywordparam.nim(1, 13) Error: 'type' is a keyword and cannot be used as a parameter name
```
---------
Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>
Co-authored-by: Emre Şafak <esafak@users.noreply.github.com>
Co-authored-by: Andreas Rumpf <araq4k@proton.me>
follows up #24871
For subscript assignments, if an overload of `[]=`/`{}=` is not found,
the LHS checks for overloads of `[]`/`{}` as a fallback, similar to what
field setters do since #24871. This is accomplished by just compiling
the LHS if the assignment overloads fail. This has the side effect that
the error messages are different now, instead of displaying the
overloads of `[]=`/`{}=` that did not match, it will display the ones
for `[]`/`{}` instead. This could be fixed by checking for `efLValue`
when giving the error messages for `[]`/`{}` but this is not done here.
The code for `[]` subscripts is a little different because of the
`mArrGet`/`mArrPut` overloads that always match. If the `mArrPut`
overload matches without a builtin subscript behavior for the LHS then
it calls `semAsgn` again with `mode = noOverloadedSubscript`. Before
this meant "fail to compile" but now it means "try to compile the LHS as
normal", in both cases the overloads of `[]=` are not considered again.
fixes#5631, fixes#8938, fixes#18855, fixes#19271, fixes#23885,
fixes#24877
`isTupleRecursive`, previously only called to give an error for illegal
recursions for:
* tuple fields
* types declared in type sections
* explicitly instantiated generic types
did not check for recursions in proc types. It now does, meaning proc
types now need a nominal type layer to recurse over themselves. It is
renamed to `isRecursiveStructuralType` to better reflect what it does,
it is different from a recursive type that cannot exist due to a lack of
pointer indirection which is possible for nominal types.
It is now also called to check the param/return types of procs, similar
to how tuple field types are checked. Pointer indirection checks are not
needed since procs are pointers.
I wondered if this would lead to a slowdown in the compiler but since it
only skips structural types it shouldn't take too many iterations, not
to mention only proc types are newly considered and aren't that common.
But maybe something in the implementation could be inefficient, like the
cycle detector using an IntSet.
Note: The name `isRecursiveStructuralType` is not exactly correct
because it still checks for `distinct` types. If it didn't, then the
compiler would accept this:
```nim
type
A = distinct B
B = ref A
```
But this breaks when attempting to write `var x: A`. However this is not
the case for:
```nim
type
A = object
x: B
B = ref A
```
So a better description would be "types that are structural on the
backend".
A future step to deal with #14015 and #23224 might be to check the
arguments of `tyGenericInst` as well but I don't know if this makes
perfect sense.
refs #24766
Detect when we track a call to a forward declaration without explicit
`raises` effects, then when the `raises` check fails for the proc, give
a hint that this forward declaration was tracked as potentially raising
any exception.
closes#24372, refs #20091
This was added in #20091 for some reason but doesn't actually work and
only makes error messages more obscure. So for now, it's disabled.
Can also be backported to 2.0 if necessary.
fixes#24179
The original fix made it so calls to `skError`/`skUnknown` (in this case
`->`, for some reason `sugar` couldn't be imported) returned an error
node, however this breaks tsug_accquote for some reason I don't
understand (it even parses as `tsug_accquote.discard`) so I've just
added a guard based on the stacktrace.
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.
split again from #24038, fixes
https://github.com/status-im/nimbus-eth2/pull/6554#issuecomment-2354977102
`var`/pointer types are no longer implicitly convertible to each other
if their element types either:
* require an int conversion or another conversion operation as long as
it's not to `openarray`,
* are subtypes with pointer indirection,
Previously any conversion below a subrange match would match if the
element type wasn't a pointer type, then it would error later in
`analyseIfAddressTaken`.
Different from #24038 in that the preview define that made subrange
matches also fail to match is removed for a simpler diff so that it can
be backported.
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)
fixes#8697, fixes#9620, fixes#23265
When matching a `template` with an `untyped` argument fails because of a
mismatching typed argument, `presentFailedCandidates` tries to sem every
single argument to show their types, but trying to type the `untyped`
argument can fail if it's supposed to use an injected symbol, so we get
an unrelated error message like "undeclared identifier".
Instead we use `tryExpr` as the comment suggests, setting the type to
`untyped` if it fails to compile. We could also maybe check if an
`untyped` argument is expected in its place and not try to compile the
expression if it is but this would require a bit of reorganizing the
code here and IMO it's better to have the information of what type it
would be if it can be typed.
fixes#23813, partially reverts #23392
Before #23392, if a `gensym` symbol was defined before a proc with the
same name in a template even with an `inject` annotation, the proc would
be `gensym`. After #23392 the proc was instead changed to be `inject` as
long as no `gensym` annotation was given. Now, to keep compatibility
with the old behavior, the behavior is changed back to infer the proc as
`gensym` when no `inject` annotation is given, however an explicit
`inject` annotation will still inject the proc. This is also documented
in the manual as the old behavior was undocumented and the new behavior
is slightly different.
fixes#3011
In https://github.com/nim-lang/Nim/pull/23532, meta fields that defined
in the object are handled.
In this PR, RefObjectTy is handled as well:
```nim
type
Type = ref object
context: ref object
```
Ref alias won't trigger mata fields checking so there won't have
cascaded errors on `TypeBase`.
```nim
type
TypeBase = object
context: ref object
Type = ref TypeBase
context: ref object
```
fixes#23419
`void` is only supported as fields of objects/tuples. It shouldn't allow
void in the array.
I didn't merge it with taField because that flag is also used for
tyLent, which is allowed in the fields of other types.
fixes#23326
In a routine declaration node in a template, if the routine is marked as
`gensym`, the compiler adds it as a new symbol to a preliminary scope of
the template. If it's not marked as gensym, then it searches the
preliminary scope of the template for the name of the routine, then when
it matches a template parameter or a gensym identifier, the compiler
replaces the name node with a symbol node of the found symbol.
This makes sense for the template parameter since it has to be replaced
later, but not really for the gensym identifier, as it doesn't allow us
to inject a routine with the same name as an identifier previously
declared as gensym (the problem in #23326 is when this is in another
`when` branch).
However this is the only channel to reuse a gensym symbol in a
declaration, so maybe removing it has side effects. For example if we
have:
```nim
proc foo(x: int) {.gensym.} = discard
proc foo(x: float) {.gensym.} = discard
```
it will not behave the same as
```nim
proc foo(x: int) {.gensym.} = discard
proc foo(x: float) = discard
```
behaved previously, which maybe allowed overloading over the gensym'd
symbols.
A note to the "undeclared identifier" error message has also been added
for a potential error code that implicitly depended on the old behavior
might give, namely ``undeclared identifier: 'abc`gensym123'``, which
happens when in a template an identifier is first declared gensym in
code that doesn't compile, then as a routine which injects by default,
then the identifier is used.
fixes#22284fixes#22282
```
Error: j(uRef, proc (config: F; sources: auto) {.raises: [].} = discard ) can raise an unlisted exception: Exception
```
The problem is that `n.typ.n` contains the effectList which shouldn't
appear in the parameter of a function defintion. We could not simply use
`n.typ.n` as `n[paramsPos]`. The effect lists should be stripped away
anyway.
fixes#23200, fixes#18866#21065 made it so `auto` proc return types remained as `tyAnything` and
not turned to `tyUntyped`. This had the side effect that anything
previously bound to `tyAnything` in the proc type match was then bound
to the proc return type, which is wrong since we don't know the proc
return type even if we know the expected parameter types (`tyUntyped`
also [does not care about its previous bindings in
`typeRel`](ab4278d217/compiler/sigmatch.nim (L1059-L1061))
maybe for this reason).
Now we mark `tyAnything` return types for routines as `tfRetType` [as
done for other meta return
types](18b5fb256d/compiler/semtypes.nim (L1451)),
and ignore bindings to `tyAnything` + `tfRetType` types in `semtypinst`.
On top of this, we reset the type relation in `paramTypesMatch` only
after creating the instantiation (instead of trusting
`isInferred`/`isInferredConvertible` before creating the instantiation),
using the same mechanism that `isBothMetaConvertible` uses.
This fixes the issues as well as making the disabled t15386_2 test
introduced in #21065 work. As seen in the changes for the other tests,
the error messages give an obscure `proc (a: GenericParam): auto` now,
but it does give the correct error that the overload doesn't match
instead of matching the overload pre-emptively and expecting a specific
return type.
tsugar had to be changed due to #16906, which is the problem where
`void` is not inferred in the case where `result` was never touched.
fixes#23186
As explained in #23186, generics can transform `genericProc[int]` into a
call `` `[]`(genericProc, int) `` which causes a problem when
`genericProc` is resemmed, since it is not a resolved generic proc. `[]`
needs unresolved generic procs since `mArrGet` also handles explicit
generic instantiations, so delay the resolved generic proc check to
`semFinishOperands` which is intentionally not called for `mArrGet`.
The root issue for
[t6137](https://github.com/nim-lang/Nim/blob/devel/tests/generics/t6137.nim)
is also fixed (because this change breaks it otherwise), the compiler
doesn't consider the possibility that an assigned generic param can be
an unresolved static value (note the line `if t.kind == tyStatic: s.ast
= t.n` below the change in sigmatch), now it properly errors that it
couldn't instantiate it as it would for a type param. ~~The change in
semtypinst is just for symmetry with the code above it which also gives
a `cannot instantiate` error, it may or may not be necessary/correct.~~
Now removed, I don't think it was correct.
Still possible that this has unintended consequences.
fixes#23002, fixes#22841, refs comments in #23097
When an identifier is ambiguous in scope (i.e. multiple imports contain
symbols with the same name), attempt resolving it through type inference
(by creating a symchoice). To do this efficiently, `qualifiedLookUp` had
to be broken up so that `semExpr` can access the ambiguous candidates
directly (now obtained directly via `lookUpCandidates`).
This fixes the linked issues, but an example like:
```nim
let on = 123
{.warning[ProveInit]: on.}
```
will still fail, since `on` is unambiguously the local `let` symbol here
(this is also true for `proc on` but `proc` symbols generate symchoices
anyway).
Type symbols are not considered to not confuse the type inference. This
includes the change in sigmatch, up to this point symchoices with
nonoverloadable symbols could be created, they just wouldn't be
considered during disambiguation. Now every proper symbol except types
are considered in disambiguation, so the correct symbols must be picked
during the creation of the symchoice node. I remember there being a
violating case of this in the compiler, but this was very likely fixed
by excluding type symbols as CI seems to have found no issues.
The pure enum ambiguity test was disabled because ambiguous pure enums
now behave like overloadable enums with this behavior, so we get a
longer error message for `echo amb` like `type mismatch: got <MyEnum |
OtherEnum> but expected T`
fixes#22753
## Future work
We should turn all the error nodes into nodes of a nkError kind, which
could be a industrious task. But perhaps we can add a special treatment
for error nodes to make the transition smooth.
refs #22605
Sym choice nodes are now only allowed to pass through semchecking if
contexts ask for them to (with `efAllowSymChoice`). Otherwise they are
resolved or treated as ambiguous. The contexts that can receive
symchoices in this PR are:
* Call operands and addresses and emulations of such, which will subject
them to overload resolution which will resolve them or fail.
* Type conversion operands only for routine symchoices for type
disambiguation syntax (like `(proc (x: int): int)(foo)`), which will
resolve them or fail.
* Proc parameter default values both at the declaration and during
generic instantiation, which undergo type narrowing and so will resolve
them or fail.
This means unless these contexts mess up sym choice nodes should never
leave the semchecking stage. This serves as a blueprint for future
improvements to intermediate symbol resolution.
Some tangential changes are also in this PR:
1. The `AmbiguousEnum` hint is removed, it was always disabled by
default and since #22606 it only started getting emitted after the
symchoice was soundly resolved.
2. Proc setter syntax (`a.b = c` becoming `` `b=`(a, c) ``) used to
fully type check the RHS before passing the transformed call node to
proc overloading. Now it just passes the original node directly so proc
overloading can deal with its typechecking.
* round out tuple unpacking assignment, support underscores
fixes#18710
* fix test messages
* use discard instead of continue
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
