Previously, the tokens that could poison a scope (`true`, `false`,
`null`) had individual fields in the scope to track whether or not
they were poisoned.
This commit sets up new machinery that instead tracks scope poisoning
dynamically using a HashMap, and which makes it possible to introduce
additional tokens to the top-level ("global") scope that are directly
resolved by the compiler by passing a map of runtime values to be
used.
With this solution, the compiler now contains all machinery required
for wiring up builtins resolution.
The set of builtins to be exposed at runtime must, however, be
constructed *outside* of the compiler and passed in. Everything is
prepared for this, but it is not yet wired up (so the only existing
builtins are the ones we already had before).
Note that this technically opens up an optimisation potential when
compiling selection operations, where the attribute set being selected
from is `builtins`. The compiler could directly resolve the builtins
and place the right values on the stack.
Change-Id: Ia7dad3c2a98703e7ea0c6ace1a722d57cc70a65c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6253
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Builtins are represented as a Rust function pointer that accepts a
vector of arguments, which represents variable arity builtins.
Change-Id: Ibab7e662a646caf1172695d876d2f55e187c03dd
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6251
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Nix functions always have a single argument and we do not yet make
efforts to optimise this in Tvix for known multi-argument functions
being directly applied.
For this reason, the call instruction is fairly simple and just calls
out to construct a new call frame.
Note that the logic for terminating the run loop has moved to the top
of the dispatch; this is because the loop run needs to be skipped if
the call frame for the current lambda has just been dropped.
Change-Id: I259bc07e19c1e55cd0a65207fa8105b23052b967
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6249
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Compiles lambda definitions of the simple form (i.e. without formals
arguments) and emits them as constants like any other value.
This does not yet implement actually invoking these functions in the VM.
Change-Id: Ie1e0a13220b68c1728be229b875f0992e685c5ef
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6247
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This structure carries context about the lambda currently being
compiled (which may well be the top-level lambda of an input AST).
Using the indirection helpers in the compiler, things like the scope,
code and constants of the function being compiled are now taken from
the current lambda context instead.
Change-Id: If5f864d826c2e72855cee4b728ea1830e9b5ac06
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6246
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This wires up most of the machinery for executing different call
frames inside of the VM and stuffs the top-level lambda which the
compiler outputs in there, as well.
Change-Id: Ib6201b3e3be1af96a4d195f6eb147f452860ffc3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6242
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This is going to carry the data for a function invocation inside of
the VM.
Change-Id: I86664563a7e35697a64294acd37ffde037fbd32d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6241
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Changes the internal compiler plumbing to not just return a chunk of
code, but the same chunk wrapped inside of a lambda value.
This is one more step towards compiling runtime lambdas.
Change-Id: If0035f8e65a2970c5ae123fc068a2396e1d8fd72
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6240
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
With these indirections in place it becomes easier to change internals
of the compiler when introducing functions, which need the compiler to
be able to target different code chunks.
Change-Id: I4eb11572a93c140b1d059ba0a5af905756745d65
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6239
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Instead of exiting the compiler at the first sight of an error,
skip any erroneous nodes and continue compiling, collecting more
errors along the way.
This paves the way for nicer error reporting in which multiple errors
can be reported at once, avoiding situations in which users are
hunting a fault error-by-error and possibly getting distracted by
less useful output.
Change-Id: I80c9a87272e33a31297167ae2eb2706a46adf15a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6236
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This starts paving the way for nicer, source-code based error
reporting.
Right now the code paths in the VM do not emit annotated errors, as we
do not yet preserve that structure from the compiler. However, error
emitting code paths in the compiler have been amended to include known
nodes.
Change-Id: I1b74410ffd891c40cd913361bd73c4336ec8aa5b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6235
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
In this commit, the string interpolation parsing is identical to
nixpkgs which makes some of the upstream Nix tests for
interpolation-related weirdness pass.
Change-Id: I3a295cfdc404c32228a54846e6efd3c0dcee5842
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6233
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
These were missing an additional level of escaping, silly oversight
caught by an upstream test.
Change-Id: I0312084475e4b88c83945614e9aa5b34c6bc3ec2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6232
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Since the latest published version of rnix-parser on crates.io, the
crate has undergone major changes which are only available in the git
repository at the moment. This commit updates the compiler to this
newer version of rnix.
Most notably, the entire AST provided by rnix is now wrapped in the
AST type system. As a result of this traversal is much nicer in many
places, especially for things like nested attribute selection.
There are a handful of smaller features missing for full feature
parity with the previous version, especially handling of path
literals, but PRs for these already exist in rnix-parser.
Change-Id: Icde6d393067976549492b7d89c4cc49e5e575fc7
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6231
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This implements `assert`, which evaluates an expression and aborts
evaluation if the value is not `true`.
At this point we should introduce eval-failed-* tests; probably
asserting against some representation of the error enum?
Change-Id: If54c8f616d89b829c1860a4835dde60a2cd70d7a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6230
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This makes for much more readable output especially when long strings
are involved.
Change-Id: I43dd73a0480535d7181a760788c42883a9b083f8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6229
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
`push_local`/`push_phantom` were worse names because they sound like
the value itself is being pushed, where in actuality it is just being
declared to the compiler.
Change-Id: Ibfda5c4c8e47d5d3262bfe005b0f1f84908a117e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6228
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
These tokens are optionally parsed as identifiers by Nix, which means
that within any scopes that resolve them the compiler needs to track
whether they have been overridden to know whether to emit the literal
instructions or resolve a variable.
This is implemented by a new concept of "scope poisoning", where the
compiler's scope structure tracks whether or not any builtin
identifiers have been overridden.
Change-Id: I3ab711146e229f843f6e1f0343385382ee0aecb6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6227
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
While full recursion through thunking is not available, there are
actually incorrect behaviours introduced by declaring before
binding (example in the newly introduced test).
This commit simplifies the implementation to avoid this issue, and
also because I intend to explore a bit more how far we can get in non
left-to-right bindings *without* introducing thunks immediately.
Change-Id: I21fd3007ac3946570639772d7d624d70bd209958
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6226
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
If an unknown variable is encountered and the with stack is not empty,
emit instructions for resolving the variable at runtime.
Change-Id: I752f4bd0025335744e4747364abd1bd34130374e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6223
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Adds an additional structure to the compiler's scope to track the
runtime "with stack", i.e. the stack of values through which
identifiers should be dynamically resolved within a with-scope.
When encountering a `with` expression, the value from which the
bindings should be resolved is pushed onto the stack and tracked by
the compiler in the "with stack", as well as with a "phantom value"
which indicates that the stack contains an additional slot which is
not available to users via identifiers.
Runtime handling of this is not yet implemented.
Change-Id: I5e96fb55b6378e8e2a59c20c8518caa6df83da1c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6217
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This name is much more sensible actually; its more than just a
collection of locals as it tracks additional scope information in the
case of Nix.
Change-Id: Ia2739bbd39aab222b1c4355e9248828973b0db43
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6216
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Note that at this point recursive bindings do not yet work in either
attrsets or let, so inheriting from the same scope is generally not
possible yet.
Change-Id: I6ca820d04b8ded5c22fb7ea18e2ec203bcaa8e9c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6215
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Straightforward implementation, evaluating the elements of an inherit
and preparing the stack so that `OpAttrs` sees all relevant values
when constructing the attribute set itself.
The emitted instructions for inheriting a lot of values from the same
attribute set are inefficient, but it's too early to say whether this
actually matters.
Change-Id: Icb55a20936d4ef77173f34433811c5fa5d2c9ecc
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6214
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
If the directory in which REPL history is stored does not exist,
gently try to create it, but do not raise an error if it doesn't work.
We may want to warn about it, but in general this sort of
non-essential feature should not cause a hard failure.
Change-Id: If4fe8db0c7893c39627efe72c9cd9ebf7ed63f04
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6213
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Using `OpAttrSelect`, the ? operator will fail when encountering a
nested value that is not an attribute set.
This however breaks valid code, such as:
{ bs = 42; } ? bs.a.b
The fix is simply to use the same operator used in the `or` statement,
which leaves a sentinal on the stack if a field is not found or the
value is not an attribute set.
Change-Id: Ib28fc8a96e6d592b4cdbc3e65ba129ad8faecd66
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6211
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
If a nested attrpath encounters a non-set value, the sentinel value
denoting a lack of next values should be emitted. This mirrors the
behaviour of Nix.
Change-Id: Ia80443d5a11243cc6d98dcab1249a3f5fdf77e27
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6210
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Not sure how exactly this snuck in, but it caused some subtle
breakages in deeply nested attribute sets.
Change-Id: I8049ce912405d3750031f79cc8d86ff1c3c02c2b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6208
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
We're confident that we're handling all branches that can reasonably
occur from valid AST, any other cases should be considered a critical
evaluator bug and panic rather than surfacing something that looks
like user error.
Change-Id: If96966eb32b8ff12fcaeb9ea3b0c8fc51b6abd11
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6205
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This is actually *tested* behaviour in C++ Nix, so we need to
implement it here, too.
Change-Id: Ic4a4659a2f04cdd928cbe78a85dae90401515371
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6199
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This adds a `disassembler` feature to the crate configuration that
traces the operations executed and the state of the stack at runtime.
This can be enabled by compiling with `--feature disassembler`.
This will also gain a more sensible layout of code slices eventually.
Change-Id: I34c15e1cd346ecc4362b5afba6bf82dd49359d20
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6193
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Using `inherit` in a let-binding can not possibly have an effect, as
the given identifier is already bound exactly the same way in the
current scope.
This introduces a subtle bug that is fixed later on, as there
actually *is* a (single) condition where these inherits are
meaningful.
Change-Id: I8b24f0edcfe80db8153bb7e86cf478d36957d6f8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6192
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This makes basic `let ... in ...` statements work correctly. It does
not yet account for the call frames pushed into the VM during function
application.
Change-Id: I67155171daf1a43011b96716dd9d1ab04b27db33
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6190
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Nix does not allow dynamic identifiers in let expressions (only in
attribute sets), but there are several different kinds of things it
considers static identifiers.
The functions introduced here put the path components of a let
expression into normalised (string) form, and surface an error about
dynamic keys if one is encountered.
Change-Id: Ia3ebd95c6f3ed3cd33b94e156930d2e9c39b6cbf
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6189
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
These expressions now leave the binding values on the stack, and clean
up the scope after the body of the expression.
While variable access is not yet implemented (as the identifier node
remains unhandled), this already gives us the correct stack behaviour.
Change-Id: I138c20ace9c64502c94b2c0f99a6077cd912c00d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6188
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
These are going to be used during compilation of `let`-expressions to
determine stack offsets for local variables.
Change-Id: Ibb79f3f1ae86650303f88eacf623ae456458de87
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6187
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Canonicalisation performs much more functionality than what C++ Nix
implements for paths, and causes some undesirable behaviour (e.g.
handling non-existant files becomes difficult, but should be possible
in literals).
Instead, the path_clean crate provides a pure normalisation method.
There is an intention to add this to Rust itself:
https://github.com/rust-lang/rfcs/issues/2208
Change-Id: I775d238136db0a52cf6b12a68985833c8fb32882
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6186
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Resolves relative paths (e.g. `./foo`) either relative to the location
of the Nix file, or relative to the working directory if none is
supplied.
Change-Id: I70ec574657b221b458015117a004b6e4a9c25a30
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6185
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
There are multiple things that can theoretically fail while resolving
a path, as some of it includes I/O. A new error variant has been added
for this and appropriate errors have been introduced.
Change-Id: Ie222245425207dabbf203166eb5ed1eec0114483
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6184
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
These two paths are the easiest to handle, as they are simply built up
from the components supplied in the text node and then normalised.
Note that the normalisation of fs::canonicalize includes symlink
resolution, which Nix does not actually do. We will need to fix that
at some point.
Change-Id: I54158f0684f197dd2a2583f7d0982d54c7619993
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6183
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
grfn pointed out in cl/6082 that this is actually the desugaring of
the write! macro, so it doesn't make sense to write it out.
Change-Id: If7c055b042ad22b034722aec1eaadba92736d684
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6180
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
grfn pointed out in cl/6069 that naming them like this makes it clear
that things are being added to the end of the state.
Change-Id: I6a23215c4fef713869a3c85b0dde1ebbda7637e9
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6179
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
For representation wrappers that are used to control the visibility of
type internals, this ensures that the wrapper does not increase the
size of the type.
In practice, the optimiser likely does this anyways but it is good to
guarantee it.
Change-Id: Ic6df7d668fe6006dfbd5b6cfcfc2088afa95b810
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6178
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This makes it possible to quickly detect code errors that might blow
up the size of the OpCode type.
Change-Id: I7662dd0aa30c4762c0f9e4fa346418c9ca8b9994
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6177
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
These can be used predominantly to emit warnings about things that the
compiler can infer, such as deprecated language features.
Change-Id: I3649c625459d7f3f95cdf42d5c651d23d66569ec
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6174
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
The parser creates this node type from literal URL values. Technically
these are deprecated and have been removed from nixpkgs.
Change-Id: I4d05034dd9b4d8348e4ed8a2bbb37c1b6ccef8bc
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6173
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This is a substantially nicer experience, immediately granting us
history, proper exiting and so on.
Change-Id: Iba4cb1713b9ac53d0799722bdbe2cd0e94a2f527
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6171
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This operator allows for accessing attribute sets (including nested
access) while also providing a default value.
This is one of the more complex operations to compile, as it needs to
keep track of a fairly large number of jumps that all need to be
patched correctly.
To make this easier to understand there's a small diagram included in
the comments.
Change-Id: Ia53bb20d8f779859bfd1692fa3f6d72af74c3a1f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6167
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This sentinel value is going to be used for certain nested accesses
into attribute sets.
There is a new instruction similar to `OpAttrsSelect` which leaves the
sentinel on the stack if a key is not found, instead of raising an
error.
Additionally, a new jump instruction makes its jump operation
conditional on finding such a sentinel value.
Change-Id: I2642f0a0bcc85bbe0ead68ea09a7dd794dbedeac
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6166
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
The only uses of the static variant were for `"name"` and `"value"`,
which are both small enough to fit into a SmolStr. The size of
NixString accomodates `String` anyways, so we may as well inline them.
Additionally smol_str is already in the dependency graph because rnix
uses it, and using it for representations of identifiers is sensible.
Change-Id: I9969312256d1657d69128e54c47dc7294a18ce58
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6165
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Having these visible more explicitly is useful while debugging.
Change-Id: I86b497883063d32792b635eb4514b7aeae484af4
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6164
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Implements the nested presence check operator for attribuet sets by
traversing the chain of lookups through instructions that push/pop
sequentially deeper attribute sets onto the stack.
Note that this commit introduces a bug in case of nested attributes
not being found, which is fixed in a later commit.
Change-Id: Ic8b4c8648736f6cb048e3aa52592e4d075bf0544
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6163
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
This makes it possible to check things like `{} ? a` with a single
level of nesting.
Change-Id: I567c36fcfd2f9e2f60071acd3ebfe56dea59b26f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6161
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
With this change, attribute set access is working as intended.
Change-Id: Ic5dbbd68aa59156106069289e7375a696909f78b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6159
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Fairly straightforward, handling the optimised representations
manually and otherwise delegating to BTreeMap.
Note that parsing of raw identifiers is not yet implemented.
Encountering an identifier node usually means that there is locals
access going on, so we need a special case for compiling a node in
such a way that an identifier's literal value ends up on the stack.
Change-Id: I13fbab7ac657b17ef3f4c5859fe737c321890c8a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6158
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
This operation is required because both sides of the logical operators
are strictly evaluated by Nix, even if the resulting value is not used
further.
For example, in our implementation of `&&`, if the left-hand side is
`true`, then the result of the expression is simply the right-hand
side value. This value must be asserted to be a boolean for the
semantics of the language to work correctly.
Change-Id: I34f5364f2a444753fa1d8b0a1a2b2d9cdf7c6700
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6157
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: grfn <grfn@gws.fyi>
Add a new `lib.rs` to tvix/eval, which `pub use`s the `interpret`
function, and all types mentioned in its return type, and then uses
*this* instead of direct `mod` statements in the `main.rs` to implement
the entrypoints to the interpreter. This is in preparation for calling
these functions from integrated benchmarking infrastructure using
Criterion, though other things (like integration tests) might want to do
that as well.
Change-Id: I7b585134a96b1c56a2ac64d2036b0e51d321bd27
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6155
Reviewed-by: tazjin <tazjin@tvl.su>
Tested-by: BuildkiteCI
Autosubmit: grfn <grfn@gws.fyi>
Similar to `||`, but inverting the left-hand side.
In other words, `a -> b` is essentially rewritten as `!a || b`.
Change-Id: I8a62da65ff070b389e46048d047a54279060a97b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6152
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
This logical operator is implemented in terms of jumping operations
and thus requires slightly different treatment than other binary
operators.
Change-Id: Ib3d768b70dd7e16014c9b47d770aa74eec60ae92
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6150
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
These expressions use simple jumps to skip the correct expression
conditionally in the bytecode by advancing the instruction pointer.
Note that these expressions are already covered by a test behind the
`nix_tests` feature flag, but adding more is probably sensible.
Change-Id: Ibe0eba95d216321c883d3b6b5816e2ab6fe7eef1
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6148
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
Wraps the string representation in an additional newtype struct with a
private field in order to hide the representation from other modules.
This is done in order to avoid accidental leakage of the internals
outside of value::string.
In fact, this caught a mistake in the compiler module which was
directly constructing an internal variant.
Change-Id: If4b627d3cff7ab9cd50ca1a3ac73245d4dcf7aef
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6147
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Wraps the attrs representation in an additional newtype struct with a
private field in order to hide the representation from other modules.
This is done in order to avoid accidental leakage of the internals
outside of value::attrs.
Change-Id: I68d1d02514aa0443df4c39801001a3f1f6cc5d5c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6146
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Ensuring that the implementation is not leaking out of the module lets
us keep things open for optimisations (e.g. empty list or pairs
through tuples).
Change-Id: I18fd9b7740f28c55736471e16c6b4095a05dd6d0
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6145
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
This is accomplished by simply delegating to the Rust implementations
of (Partial)Ord and (Partial)Eq, which are implemented for Value and
underlying wrapper types to behave like they do in Nix.
To ease the implementation overhead, a new comparison operator macro
has been added to the VM module.
Incomparable types will raise a new error variant when a comparison is
attempted, containing both supplied types. This mimics the information
carried in the error thrown by C++ Nix.
Change-Id: Ia19634d69119d40722f3ca672387bc3a80096998
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6143
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
This can now fully delegate to PartialEq of Value
Change-Id: Iaa9f4ec9b8830d516d72f83a93ab2df9a6e5697c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6142
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
The underlying implementation does a few tricks based on which pair of
attrset representations is encountered.
Particularly the effect of short-circuiting the empty cases might be
relevant in nixpkgs/NixOS, due to the use of lib.optionalAttrs.
Change-Id: I22b978b1c69af12926489a71087c6a6219c012f3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6140
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
I assumed that `Ord` is a marker trait like `Eq`, but it actually has
a member. Without this ordering was incoherent.
Change-Id: Id37cbdf333daf748d29b85243046c7e061b1ce29
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6139
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Instead of constructing another runtime value representing the pair on
which to perform arithmetic, implement the same logic in the shape of
a macro.
This is designed to be compatible with operators like `+` that work
both as an arithmetic operator AND as an operator on another pair of
types.
Change-Id: I1c83649ead6117f811f1fb45482d0cadf811125e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6136
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Nix displays a maximum of 5 digits for floating points.
Change-Id: Ifa3c0d96fa0b24e3be8f94dfebc99e602a258355
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6133
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Once we have full coverage they should be enabled by default.
Change-Id: Iace9e1ae9a9f901a0979ad336434004b8028fe8a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6129
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
When printing strings as identifiers (in attribute sets), the string
should only be quoted and escaped if it contains escape characters.
Change-Id: If2bcfa1e93dc8f00be4d7a57ec1d82fc679103c3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6127
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
This adds scaffolding code for running the Nix language test suite.
The majority of eval-okay-* tests should eventually be runnable as-is
by Tvix, however the eval-fail-* tests might not as we intend to have
more useful error messages than upstream Nix.
Change-Id: I4f3227f0889c55e4274b804a3072850fb78dd1bd
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6126
Tested-by: BuildkiteCI
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: grfn <grfn@gws.fyi>
Nix strings displayed to users must be escaped the same way as they
are in C++ Nix. This adds the scaffolding for escapes, but is most
likely not yet complete.
Change-Id: Icfdcb2ac98d292c567ba894a92b6529a53e0cc17
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6124
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Instead of comparing the enum variants (which does not yield useful
behaviour), compare &str representations of the string instead.
Change-Id: I5e94b5f6c91b4561e1bc7c36d586f3d23c243764
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6112
Tested-by: BuildkiteCI
Reviewed-by: eta <tvl@eta.st>
For cases where the strings are statically known (such as the
oft-occuring name/value), this can be a useful optimisation.
It's also much more convenient in tests.
Change-Id: Ie462b684805bd4986ea5e85ca4bff663bc2d3c3c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6111
Tested-by: BuildkiteCI
Reviewed-by: eta <tvl@eta.st>
These do not yet test nested attribute sets; we need to add some more
inspection primitives first.
Change-Id: Icfc99bf17c73ebefc0d882a84f0ca73ec688a54d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6110
Reviewed-by: eta <tvl@eta.st>
Tested-by: BuildkiteCI
With this change, nested attribute sets can now be created from
literals.
This required some logic for dealing with cases where at a deeper
nesting point a literal attribute set was constructed from an
optimised representation.
For example, this is valid Nix code:
```nix
{
a = {}; # creates optimised empty representation
a.b = 1; # wants to add a `b = 1` to it
b = { name = "foo"; value = "bar"; }; # creates optimised K/V repr
b.foo = 42; # wants to add an additional `foo = 42`
}
```
In these cases, the attribute set must be coerced to a map
representation first which is achieved by the new internal
NixAttr::map_mut helper.
Change-Id: Ia61d3d9d14c4e0f5e207c00f6a2f4daa3265afb2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6109
Reviewed-by: eta <tvl@eta.st>
Tested-by: BuildkiteCI
The internal optimisations of the set representation were previously
leaking into the VM, which is highly undesirable.
Keeping it encapsulated allows us to do additional optimisations
within value::attrs without being concerned about its use in the VM.
Change-Id: I7e7020bb0983b9d355d3db747b049b2faa60131f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6108
Reviewed-by: eta <tvl@eta.st>
Tested-by: BuildkiteCI
There are multiple points where an insertion needs to be done into an
attribute set, but copying the key or checking for presence before
insertion should be avoided
As that is a little bit noisy, it's been factored out into a helper
function in this commit.
Change-Id: Ibcb054ebeb25a1236c06c812f47c8e74180d4fc9
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6107
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This can construct non-overlapping nested attribute sets (i.e. `{ a.b
= 1; b.c = 2; }`, but not `{ a.b = 1; a.c = 2; }`).
In order to do the latter, it's necessary to gain the ability to
manipulate the in-progress attribute set construction. There's
multiple different options for this ...
Change-Id: If1a762a720b175e8eb4216cbf96a7434d22640fb
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6106
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
There are some notions of equality (due to e.g. different backing
variants for types, or Nix particularities) that don't work correctly
when deriving PartialEq.
Change-Id: Ide83ae67d051cc0b3ca89cefb283f17d0207acce
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6105
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This is required for constructing nested attribute sets at runtime.
There'll be quite a lot of optimisation potential with this solution
eventually, if it should turn out to be a bottleneck.
This introduces a conceptual change, in that the `Value` enum is now
an enum representing "all runtime values" instead of "all Nix language
types". This makes sense in general, as this type will also contain
Chunk representations etc. which are not exposed to users.
Change-Id: Ic5f72b2a0965b146c6a451efad34c6a81ca1aad8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6103
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
For name/value pairs (which occur extremely often in Nix and make up a
significant chunk of the runtime cost of evaluating nixpkgs) we
substitute an optimised representation.
For now this will only be used if the name/value pair keys were
specified as literal identifiers or strings (i.e. if chunks are
encountered as keys they are not forced and a normal attribute set
backed by a map will be constructed).
Change-Id: Ic79746c323e627528bd58b1a6024ee8d0aff7858
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6102
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
Users may construct a pair that falls into the name/value optimisation
but where `name` is not actually a string, as from the language
perspective there is nothing special about this attribute set.
We also can not conditionally apply this by forcing the key at this
point, as this would change the language semantics.
Therefore, the name in the optimised representation is also carried as
`Value`.
Change-Id: I5be8a4c98ba19ebdfb7203a929f714a04492512e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6101
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI
This adds a new instruction which assembles an interpolated string
from a specified number of fragments, which are already going to be
located on the stack in the right position.
This will raise a type error if any of the fragments do not evaluate
to a string.
Change-Id: I5756248fa3e9fcc3d063c14db40b332f7e20a588
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6098
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This sets up the scaffolding for compiling interpolation, but those
instructions do not yet exist.
Change-Id: Ife41bbbf432d9661abe566c92437409dd0da44e7
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6097
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
There might be more logic in the future to encapsulate different
backing implementations of lists as well.
Change-Id: Ib7064fab48bf88b0c8913b0ecfa2108177c7c9fd
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6093
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
Implements attribute set literals without nesting. Technically this
already supports dynamic key fragments (evaluating to strings), though
the only way to create these (interpolation) is not yet implemented.
However, creating simple attribute sets like `{ }`, or `{ a = 15; }`
or `{ a = 10 * 2; }` works.
Recursive attribute sets are not yet implemented as we do not have any
kind of scope access yet anyways.
This is implemented using a new instruction that creates an attribute
set with a given number of elements by popping key/value pairs off the
stack.
Change-Id: I0f9aac7a131a112d3f66b131297686b38aaeddf2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6091
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Deriving Ord/Eq is required for the ordered BTreeMaps. Once interning
is implemented this will require some extra magic for the sort order,
but that's fine.
Change-Id: I0c654648eb3609a4a01d84868c25f43a4d35bc2e
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6089
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This representation should match what the Nix REPL shows for result
values.
Change-Id: If3143d969fcdc123a6029e2aeb7bbd6ae51aeb71
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6082
Tested-by: BuildkiteCI
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: grfn <grfn@gws.fyi>
This isn't relevant to the value type itself.
Change-Id: I678bc92a8a530b1081ed498bf3ff7925217bcc01
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6081
Tested-by: BuildkiteCI
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: grfn <grfn@gws.fyi>
These are a bit tricky to implement because Nix technically treats
them as identifiers, and only if the identifier is not explicitly
overridden within the scope does it yield the expected literal values.
Note that weirdness even occurs with scopedImport.
Change-Id: Ie55723405ccfcc25da37c5a08fa3332f37cf9ae5
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6080
Tested-by: BuildkiteCI
Autosubmit: tazjin <tazjin@tvl.su>
Reviewed-by: grfn <grfn@gws.fyi>
Implements simple arithmetic operations (+, -, *, /).
There is some scaffolding included to pop and coerce pairs of numbers,
as the Nix language will let arithmetic operators apply to arbitrary
pairs of number types (always resulting in floats if the types are
mixed).
Change-Id: I5f62c363bdea8baa6ef812cc64c5406759d257cf
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6074
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This creates a REPL which outputs compiled bytecode, constants, and VM
results for code snippets.
Change-Id: If63f79a961456afd6a4cdf59b994107ff7ab8b47
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6072
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Autosubmit: tazjin <tazjin@tvl.su>
This can't do anything other than compute a single literal, for now
Change-Id: Ia28f9da51c906b590a198e77a4ca5d45a871106b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6071
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
This compiler can only take care of very trivial literals so far.
Change-Id: I9dfac75a801b7235f868061a979ae24159fe1425
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6070
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
