This fixes an oversight with a change that I made a while ago.
Basically, these two snippets should both compile. Currently the
`varargs` version will fail.
```nim
template s(d: typed)=discard
proc something()=discard
proc something(x:int)=discard
s(something)
```
```nim
template s(d: varargs[typed])=discard
proc something()=discard
proc something(x:int)=discard
s(something)
```
Potentially unrelated, but this works currently for some reason:
```nim
template s(a: varargs[typed])=discard
proc something()=discard
proc something(x:int)=discard
s:
something
```
also, this works:
```nim
template s(b:untyped, a: varargs[typed])=discard
proc something()=discard
proc something(x:int)=discard
s (g: int):
something
```
but this doesn't, and the error message is not what I would expect:
```nim
template s(b:untyped, a: varargs[typed])=discard
proc something()=discard
proc something(x:int)=discard
s (g: int), something
```
So far as I can tell, none of these issues persist for me after the code
changes in this PR.
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.}
```
…hich conveys effects beyond its module scope for C/C++
codegen(suppresses current UnusedImport warning)
Just a minor inconvenience working in the area of C/C++ integration I
guess, but here we go:
I noticed receiving ```UnusedImport``` warnings for modules having only
```passC```/```passL```/```compile``` pragmas around. I gather the
compiler cannot actually infer those modules being unused as they *may*
have consequences for the whole build process (as they did in my simple
case).
Thus, I hereby suggest adding the `sfUsed` flag to the respective module
in order to suppress the compiler's warning.
I reckon other pragmas should be put into consideration as well: I will
keep up the investigation with PR followups.
fixes#22909
required by https://github.com/nim-lang/Nim/pull/23267
```nim
proc foo: string =
assert false
result = ""
```
In the function `foo`, `assert false` raises an exception, which can
cause `result` to be uninitialized if the default result initialization
is optimized out
fixes#23247closes#23251 (which accounts for why the openarray type is lifted
because ops are lifted for openarray conversions)
related: https://github.com/nim-lang/Nim/pull/18713
It seems to me that openarray doesn't own the data, so it cannot destroy
itself. The same case should be applied to
https://github.com/nim-lang/Nim/issues/19435. It shouldn't be destroyed
even openarray can have a destructor. A cleanup will be followed for
https://github.com/nim-lang/Nim/pull/19723 if it makes sense.
According to https://github.com/nim-lang/Nim/pull/12073, it lifts
destructor for openarray when openarray is sunk into the function, when
means `sink openarray` owns the data and needs to destroy it. In other
cases, destructor shouldn't be lifted for `openarray` in the first place
and it shouldn't destroy the data if it doesn't own it.
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
fixes#22597
```nim
proc autoToOpenArray*[T](s: Slice[T]): openArray[T] =
echo "here twice"
result = toOpenArray(s.p, s.first, s.last)
```
For functions returning openarray types, `fixupCall` creates a temporary
variable to store the return value: `let tmp = autoToOpenArray()`. But
`genOpenArrayConv` cannot handle openarray assignements with side
effects. It should have stored the right part of the assignment first
instead of calling the right part twice.
fixes#18125
Previously a tuple type like `(T, int)` would match an expected tuple
type `(U, int)` if `T` is a subtype of `U`. This is wrong since the
codegen does not handle type conversions of individual tuple elements in
a type conversion of an entire tuple. For this reason the compiler
already does not accept `(float, int)` for a matched type `(int, int)`,
however the code that checked for which relations are unacceptable
checked for `< isSubtype` rather than `<= isSubtype`, so subtypes were
not included in the unacceptable relations.
Update: Now only considered unacceptable when inheritance is used, as in
[`paramTypesMatch`](3379d26629/compiler/sigmatch.nim (L2252-L2254)).
Ideally subtype relations that don't need conversions, like `nil`,
`seq[empty]`, `range[0..5]` etc would be their own relation
`isConcreteSubtype` (which would also allow us to differentiate with
`openArray[T]`), but this is too big of a refactor for now.
To compensate for this making things like `let x: (Parent, int) =
(Child(), 0)` not compile (they would crash codegen before anyway but
should still work in principle), type inference for tuple constructors
is updated such that they call `fitNode` on the fields and their
expected types, so a type conversion is generated for the individual
subtype element.
fixes#17163, refs #23204
Types that aren't `tyRange` and are bigger than 16 bits, so `int32`,
`uint64`, `int` etc, are disallowed as array index range types.
`tyRange` is excluded because the max array size is backend independent
(except for the specific size of `high(uint64)` which crashes the
compiler) and so there should still be an escape hatch for people who
want bigger arrays.
This PR modifies `specializeResetT` so that it generates the proper
reset code for range types. I've tested it in the examples for issues
#23214 and #22462 as well as our codebase, and it seems to fix the
issues I had been experiencing.
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#23177
`changeType` doesn't perform range checks to see if the expression fits
the new type [if the old type is the same as the new
type](62d8ca4306/compiler/semexprs.nim (L633)).
For `nkIntLit`, we previously set the type to the concrete base of the
expected type first, then call `changeType`, which works for things like
range types but not bare types of smaller bit size like `int8`. Now we
don't set the type (so the type is nil), and `changeType` performs the
range check when the type is unset (nil).
fixes#22775
It's pre-existing that [`prepareOperand` doesn't typecheck expressions
which have
types](a4f3bf3742/compiler/sigmatch.nim (L2444)).
Templates can take typed subscript expressions, transform them into
calls to `[]`, and then have this `[]` not be resolved later if the
expression is nested inside of a call argument, which leaks an untyped
expression past semantic analysis. To prevent this, don't transform any
typed subscript expressions into calls to `[]` in templates. Ditto for
curly subscripts (with `{}`) and assignments to subscripts and curly
subscripts (with `[]=` and `{}=`).
This is in reference to a [feature
request](https://github.com/nim-lang/Nim/issues/22142) that I posted.
I'm making this PR to demonstrate the suggested change and expect that
this should be scrutinized
---------
Co-authored-by: Bung <crc32@qq.com>
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
why ?
- We already have an emit that does the same thing
- The name asm itself is a bit confusing, you might think it's an alias
for asm.js or something else.
- The asm keyword is used differently on different compiler targets (it
makes it inexpressive).
- Does anyone (other than some compiler libraries) use asm instead of
emit ? If yes, it's a bit strange to use asm somewhere and emit
somewhere. By making the asm keyword for js target deprecated, there
would be even less use of the asm keyword for js target, reducing the
amount of confusion.
- New users might accidentally use a non-universal approach via the asm
keyword instead of emit, and then when they learn about asm, try to
figure out what the differences are.
see https://forum.nim-lang.org/t/10821
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
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`
Filling in some more logic in `typeRel` that I came across when poking
the compiler in another PR. Some of the cases where `typeRel` returns an
"incorrect" result are actually common, but `sumGeneric` ends up
breaking the tie correctly. There isn't anything wrong with that
necessarily, but I assume that it's preferred these functions behave
just as well in isolation as they do when integrated.
I will be following up this description with specific examples.
