The pseudo-constructor `Value::mkAttrs` would previously be called on an
default-constructed (under-initialized) `Value` to create a properly
initialized `Value` that represents an attribute set. This change
removes mkAttrs and constructs attr `Value`s directly.
Change-Id: I11cd801eefecd454a7a5b6229d6770d06a6a6964
That struct has been annoying me since I've encountered it. There is no
reason for having to track all these symbols out of band in the state.
Change-Id: I5c2c0d8174af0a51f9b456cc3651d8203a406d09
thunk values are shareable, and we can represent invalid/uninitialized
values with a special bit pattern that makes no sense otherwise. there
is no need to keep allocating values on the heap, instead we can treat
values like reference-counted smart pointers to heap objects, which in
turn lets us save a lot of allocations and, ultimately, gc heap space.
compared to our baseline (main of 2025-09-27) we save 15%+ memory on a
system rebuild and 17% on nix search. eval time regresses by ~3% for a
system rebuild, while nix search is 7% faster. further optimization is
probably possible (but for now this will just have to be good enough).
Change-Id: Ib6c47acdbe2fac4f76a83c2269f16f30ef66b2e1
on its own this is not very useful, but having accessors for every value
kind is a prerequisite for doing smart things with Value than the union.
the net effect for now is only to add a few parentheses across the tree.
Change-Id: I88688ac09eb08495dad1eb221034ca540f094950
`fetchGit` has been modified a long time ago to use fetchTree, however,
we don't care about `lastModified` because we are not in a flake
context, this hack introduces a `git-locked` type of input that only
cares about `narHash` being present. This is needed to avoid fetching
the remote repo each time `fetchGit` is evaluated whith the result
present in the store.
Change-Id: I521c6fcccf8cf12945594f205d7fd4c8c2cf89e9
Inspired by cl/3191 and
https://git.lix.systems/delroth/lix/commit/ae0247cbb4fc739ab013dc87d02e5f3191cf25ab.
`coerceToString` takes now an enumeration that lives in `value.hh`, this
enumeration is meant to represent increasing subsets of behaviors, e.g.
any level above Strict should do what the previous levels do and extra
behavior until `ToString`, which transforms many Nix values into an
arbitrary string representation, e.g. `null` to `""`.
Change-Id: Ief7a4756e8c0660e197623efebeaf07710746ec7
Signed-off-by: Raito Bezarius <raito@lix.systems>
Co-authored-by: Pierre Bourdon <delroth@gmail.com>
otherwise lix may crash when e.g. nix search receives invalid regex.
we now also give better error messages for regex errors during eval.
fixes#803
Change-Id: Icc7c578ff488ba520efac5d898572ccf4486e9a8
This cleans up includes that clangd reports as unused, usually by deleting the offending include. The process was to delete an include and see if it still builds. If not, try to find a more specific include(s) that works, that was previously transitively included. If the original include seems intended to re-export said transitive include, mark the transitive include as `// IWYU pragma: export`. Otherwise, replace the original include with the transitive include(s). If none of the above applies, because the original file depends on code directly in the include somehow, or the direct include is an external dependency that cannot be modified, restore the original include and mark it as `// IWYU pragma: keep`.
Change-Id: I5ce3d34dad76b0cad0a6a7990fea13add393aad3
Documenting fetchTree is an exercise in frustration because of the sheer
amount of stringly typed everything in it. I do not know which fields
exist without reading the entirety of libfetchers. However, we can write
something slightly perfunctory but at least perhaps somewhat helpful
documentation-wise.
Fixes: https://git.lix.systems/lix-project/lix/issues/609
Change-Id: I991391b53fcd69172dbc7efb9d384e62bc847b91
Specifically, for errors where the provided and expected hashes differ.
Also, I've updated `fetchTarball`'s docs to explain the allowed values
for the `sha256` attribute.
Change-Id: Ic9aa777dc0a3c1ccdb4c98048745067f529bd986
this finally gives us a witness type we can use to prove that a certain
call graph subtree can't be used in kj promises using only a single new
assumption: if EvalState& is never held as a reference member of a type
and instead only ever passes as an argument or held on the stack we can
be certain that anything that has access to en EvalState ref must never
be run inside a promise and, crucially, that anything that doesn't have
access to an EvalState& *can* be run inside a promise without problems.
Change-Id: I6c15ada479175ad7e6cd3e4a729a5586b3ba30d6
this will let us pass the capability to create debuggable eval errors
without having to pass an entire EvalState. we could pass symbols and
debug states around just as easily, but if we add new capabilities to
our debugger we might have to change many more places than with this.
Change-Id: I2f8893012e5d98a986ef1fc888234c2dd8d5e096
not all of these are even used by eval itself. notably sWith wasn't used
at all, sEpsilon was only used by the eval cache one layer up, and other
attributes are used in places even further away from eval itself. we can
keep this commingling for now, but eventually we should clean it up too.
Change-Id: I5684ac614361bf008e04472130c6c02082b4c2d7
clangd broke because it can't look through symlinks. compile_commands
manipulation does not fix it, clangd configuration does not fix it, a
vfs overlay does not fix it, and while a combination of those can fix
it with a bind mount in place that's just too cursed to even consider
clangd bug: https://github.com/llvm/llvm-project/issues/116877
Change-Id: I8e3e8489548eb3a7aa65ac9d12a5ec8abf814aec
skye