ref https://en.cppreference.com/w/cpp/error/exception/what
> Pointer to a null-terminated string with explanatory information. The
pointer is guaranteed to be valid at least until the exception object
from which it is obtained is destroyed, or until a non-const member
function on the exception object is called.
The pointer is only valid before `CStdException as e` is destroyed
Old examples are broken on macOS arm64
```
/Users/blue/Desktop/nimony/test4.nim(38) test4
/Users/blue/Desktop/nimony/test4.nim(26) fn
/Users/blue/.choosenim/toolchains/nim-#devel/lib/std/assertions.nim(41) failedAssertImpl
/Users/blue/.choosenim/toolchains/nim-#devel/lib/std/assertions.nim(36) raiseAssert
/Users/blue/.choosenim/toolchains/nim-#devel/lib/system/fatal.nim(53) sysFatal
Error: unhandled exception: /Users/blue/Desktop/nimony/test4.nim(26, 3) `$b == "foo2"` [AssertionDefect]
```
- `/` is now a hotkey to jump to the search
- Search results now are in line with the page (previously on small
screens it would be off centre)
- Jumping to a search result inside the page or via TOC will now hide
the search results (previously the results got in the way)
Example site here: https://tranquil-scone-c159b6.netlify.app/main.html
refs #24503
Infinite recursions currently are not tracked separately from infinite
loops, because they also increase the loop counter. However the max
infinite loop count is very high by default (10 million) and does not
reliably catch infinite recursions before consuming a lot of memory. So
to protect against infinite recursions, we separately track call depth,
and add a separate option for the maximum call depth, much lower than
the maximum iteration count by default (2000, the same as
`nimCallDepthLimit`).
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
closes https://github.com/nim-lang/RFCs/issues/380, fixes#4773, fixes
#14729, fixes#16755, fixes#18150, fixes#22984, refs #11167 (only some
comments fixed), refs #12620 (needs tiny workaround)
The compiler gains a concept of root "nominal" types (i.e. objects,
enums, distincts, direct `Foo = ref object`s, generic versions of all of
these). Exported top-level routines in the same module as the nominal
types that their parameter types derive from (i.e. with
`var`/`sink`/`typedesc`/generic constraints) are considered attached to
the respective type, as the RFC states. This happens for every argument
regardless of placement.
When a call is overloaded and overload matching starts, for all
arguments in the call that already have a type, we add any operation
with the same name in the scope of the root nominal type of each
argument (if it exists) to the overload match. This also happens as
arguments gradually get typed after every overload match. This restricts
the considered overloads to ones attached to the given arguments, as
well as preventing `untyped` arguments from being forcefully typed due
to unrelated overloads. There are some caveats:
* If no overloads with a name are in scope, type bound ops are not
triggered, i.e. if `foo` is not declared, `foo(x)` will not consider a
type bound op for `x`.
* If overloads in scope do not have enough parameters up to the argument
which needs its type bound op considered, then type bound ops are also
not added. For example, if only `foo()` is in scope, `foo(x)` will not
consider a type bound op for `x`.
In the cases of "generic interfaces" like `hash`, `$`, `items` etc. this
is not really a problem since any code using it will have at least one
typed overload imported. For arbitrary versions of these though, as in
the test case for #12620, a workaround is to declare a temporary
"template" overload that never matches:
```nim
# neither have to be exported, just needed for any use of `foo`:
type Placeholder = object
proc foo(_: Placeholder) = discard
```
I don't know what a "proper" version of this could be, maybe something
to do with the new concepts.
Possible directions:
A limitation with the proposal is that parameters like `a: ref Foo` are
not attached to any type, even if `Foo` is nominal. Fixing this for just
`ptr`/`ref` would be a special case, parameters like `seq[Foo]` would
still not be attached to `Foo`. We could also skip any *structural* type
but this could produce more than one nominal type, i.e. `(Foo, Bar)`
(not that this is hard to implement, it just might be unexpected).
Converters do not use type bound ops, they still need to be in scope to
implicitly convert. But maybe they could also participate in the nominal
type consideration: if `Generic[T] = distinct T` has a converter to `T`,
both `Generic` and `T` can be considered as nominal roots.
The other restriction in the proposal, being in the same scope as the
nominal type, could maybe be worked around by explicitly attaching to
the type, i.e.: `proc foo(x: T) {.attach: T.}`, similar to class
extensions in newer OOP languages. The given type `T` needs to be
obtainable from the type of the given argument `x` however, i.e.
something like `proc foo(x: ref T) {.attach: T.}` doesn't work to fix
the `ref` issue since the compiler never obtains `T` from a given `ref
T` argument. Edit: Since the module is queried now, this is likely not
possible.
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
It seems exportcpp was implemented in v1.0 but there is no documentation
about it excepts changelog.
`noinline` is used in many procedures in Nim code but there is also no
documentation about it.
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
Followup to #24154, packages aren't ready for macos 14 (M1/ARM CPU) yet
and it seems to be preview on azure, so upgrade to macos 13 for now.
Macos 12 gives a warning:
```
You are using macOS 12.
We (and Apple) do not provide support for this old version.
It is expected behaviour that some formulae will fail to build in this old version.
It is expected behaviour that Homebrew will be buggy and slow.
Do not create any issues about this on Homebrew's GitHub repositories.
Do not create any issues even if you think this message is unrelated.
Any opened issues will be immediately closed without response.
Do not ask for help from Homebrew or its maintainers on social media.
You may ask for help in Homebrew's discussions but are unlikely to receive a response.
Try to figure out the problem yourself and submit a fix as a pull request.
We will review it but may or may not accept it.
```
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.
fixes#5395
Previously values of `const` statements used the same scope as the
`const` statement itself, meaning variables could be declared inside
them and referred to in other statements in the same block. Now each
`const` value opens its own scope, so any variable declared in the value
of a constant can only be accessed for that constant.
We could change this to open a new scope for the `const` *section*
rather than each constant, so the variables can be used in other
constants, but I'm not sure if this is sound.
Adds a few fixes for when using code blocks with lines numbered
- Use CSS variables for the colours so that it works in dark mode
- Don't turn on normal table effects like hover and smaller font when
its a line number table
- With dochack.nim, don't add a clipboard copy button for the line
numbers at the side
[Example page showing the
changes](https://66dcde6e4a655efb70771d9a--dazzling-kitten-6c3419.netlify.app/)
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#15314, fixes#24002
The OpenSym behavior first added to generics in #23091 now also applies
to templates, since templates can also capture symbols that are meant to
be replaced by local symbols if the context imports symbols with the
same name, as in the issue #24002. The experimental switch
`templateOpenSym` is added to enable this behavior for templates only,
and the experimental switch `openSym` is added to enable it for both
templates and generics, and the documentation now mainly mentions this
switch.
Additionally the logic for `nkOpenSymChoice` nodes that were previously
wrapped in `nkOpenSym` now apply to all `nkOpenSymChoice` nodes, and so
these nodes aren't wrapped in `nkOpenSym` anymore. This means
`nkOpenSym` can only have children of kind `nkSym` again, so it is more
in line with the structure of symchoice nodes. As for why they aren't
merged with `nkOpenSymChoice` nodes yet, we need some way to signal that
the node shouldn't become ambiguous if other options exist at
instantiation time, we already captured a symbol at the beginning and
another symbol can only replace it if it's closer in scope and
unambiguous.
refs https://github.com/nim-lang/Nim/pull/23873#discussion_r1687995060,
fixes#23386, fixes#23385, supersedes #23572
Turns the `nfOpenSym` node flag implemented in #23091 and extended in
#23102 and #23873, into a node kind `nkOpenSym` that forms a unary node
containing either `nkSym` or `nkOpenSymChoice`. Since this affects
macros working on generic proc AST, the node kind is now only generated
when the experimental switch `genericsOpenSym` is enabled, and a new
node flag `nfDisabledOpenSym` is set to the `nkSym` or `nkOpenSymChoice`
when the switch is not enabled so that we can give a warning.
Now that the experimental switch has more reasonable semantics, we
define `nimHasGenericsOpenSym2`.
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.
I've been working on making some basic cuda examples work, both with
cuda (nvcc) and with AMD HIP (hipcc) https://github.com/monofuel/hippo
- hipcc is just a drop-in replacement for clang and works out of the box
with clang settings in Nim. hipcc is capable of compiling for AMD ROCm
or to CUDA, depending on how HIP_PLATFORM is set.
- nvcc is a little quirky. we can use `-x cu` to tell it to handle nim's
`.cpp` files as if they were `.cu` files. nvcc expects all backend
compiler flags to be wrapped with a special `-Xcompiler=""` flag when
compiling and also when linking.
I manually tested on a linux desktop with amd and a laptop with nvidia.
fixes#4695
ref https://github.com/nim-lang/Nim/pull/15818
Since `nkState` is only for the main loop state labels and `nkGotoState`
is used only for dispatching the `:state` (since
https://github.com/nim-lang/Nim/pull/7770), it's feasible to rewrite the
loop body into a single case-based dispatcher, which enables support for
JS, VM backend. `nkState` Node is replaced by a label and Node pair and
`nkGotoState` is only used for intermediary processing. Backends only
need to implement `nkBreakState` and `closureIterSetupExc` to support
closure iterators.
pending https://github.com/nim-lang/Nim/pull/23484
<del> I also observed some performance boost for C backend in the
release mode (not in the danger mode though, I suppose the old
implementation is optimized into computed goto in the danger mode)
</del>
allPathsAsgnResult???
Nim manual says:
> When using the Cpp backend, params marked as byref will translate to
cpp references `&`
But how `byref` pragma translate to depends on whether it is used with
`importc` or `importcpp`.
When `byref` pragma used with `importc` types and compiled with the Cpp
backend, it is not traslated to cpp reference `&`.
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
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>
This PR modernises the NEP1 style guide to prefer hanging indent over
vertial alignment for long code statements while still allowing
alignment in legacy code.
The change is based on research and study of existing style guides for
both braced and indented languages that have seen wide adoption as well
as working with a large Nim codebase with several teams touching the
same code regularly.
The research was done as part of due diligence leading up to
[nph](https://github.com/arnetheduck/nph) which uses this style
throughout.
There are several reasons why hanging indent works well for
collaboration, good code practices and modern Nim features:
* as NEP1 itself points out, alignment causes unnecessary friction when
refactoring, adding/removing items to lists and otherwise improving code
style or due to the need for realignment - the new recommendation aligns
NEP1 with itself
* When collaborating, alignment leads to unnecessary git conflicts and
blame changes - with hanging indent, such conflicts are minimised.
* Vertical alignment pushes much of the code to the right where often
there is little space - when using modern features such as generics
where types may be composed of several (descriptively named) components,
there is simply no more room for parameters or comments
* The space to the left of the alignemnt cannot productively be used for
anything (unlike on the right, where comments may be placed)
* Double hanging indent maintaines visual separation between parameters
/ condition and the body that follows.
This may seem like a drastic change, but in reality, it is not:
* the most popular editor for Nim (vscode) already promotes this style
by default (if you press enter after `(`, it will jump to an indent on
the next line)
* although orthogonal to these changes, tools such as `nph` can be used
to reformat existing code should this be desired - when done in a single
commit, `git blame` is not lost and neither are exsting PRs (they can
simply be reformatted deterministically) - `nph` is also integrated with
vscode.
* It only affects long lines - ie most code remains unchanged
Examples of vertical alignment in the wild, for wildly successful
languages and formatters:
* [PEP-8](https://peps.python.org/pep-0008/#indentation)
*
[black](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html#how-black-wraps-lines)
* [prettier](https://prettier.io/docs/en/)
The above examples are useful mainly to show that hanging-indent
_generally_ is no impediment to efficient code reading and on the whole
is an uncontroversial choice as befits the standard library.
(Inspired by this pragma in nir asm PR)
`inlineAsmSyntax` pragma allowing specify target inline assembler syntax
in `asm` stmt.
It prevents compiling code with different of the target CC inline asm
syntax, i.e. it will not allow gcc inline asm code to be compiled with
vcc.
```nim
proc nothing() =
asm {.inlineAsmSyntax: "gcc".} """
nop
"""
```
The current C(C++) backend implementation cannot generate code for gcc
and for vcc at the same time. For example, `{.inlineAsmSyntax: "vcc".}`
with the ICC compiler will not generate code with intel asm syntax, even
though ICC can use both gcc-like asm and vcc-like. For implement support
for gcc and for vcc at the same time in ICC compiler, we need to
refactor extccomp
---------
Co-authored-by: Andreas Rumpf <rumpf_a@web.de>
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>
