Commit Graph

778 Commits (2ae33a1dfac5cb64107b0affcefad52dac6eb3d3)

Author SHA1 Message Date
Mike Gerwitz 2ae33a1dfa tamer: asg::graph::object: ObjectIndexTo and ObjectIndexRelTo
The graph's ontology is defined in the direction of the edge: from OA
to OB.  This is enforced by the type system to ensure that no code path is
able to generate an invalid graph.

But that also makes it very difficult to work with a generic source to a
specific target.

This introduces a `ObjectIndexRelTo` trait that says whether `Self` is able
to be related to some `ObjectKind` `OB`, implements it for `ObjectIndex
where ObjectRelTo<OB>`, and introduces a new semi-opaque type
`ObjectIndexTo` that allows for the source `ObjectIndex` to be generic.

This then redefines some existing graph primitives in terms of
`ObjectIndexRelTo`, in particular creating edges, so that `ObjectIndex` can
be used as today, and the new `ObjectIndexTo` can be used in the same way
with the same API, without violating the graph ontology.

This will be used by `AirAggregate` to create dynamic targets for rooting
and splicing/expansion.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz eebacb52cc tamer: asg::air::AirAggregate: Remove waiting AirExprAggregate
To simplify things in support of upcoming changes, we'll just instantiate a
new one as needed.  This doesn't have an appreciable performance impact, so
the optimization is premature.  It was done just because it was more of the
same that TAMER was already doing, but now it's making things more
difficult.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz b1ce7aaf29 tamer: asg::air: AirAggregateCtx: New AirAggregate::Context
Future changes to `AirAggregate` are going to require additional context (a
stack, specifically), but the `Context` is currently utilized
by `Asg`.  This introduces a layer of abstraction that will allow us to add
the stack.

Alongside these changes, `ParseState` has been augmented with a `PubContext`
type that is utilized on public APIs, both maintaining BC with existing code
and keeping these implementation details encapsulated.

This does make a bit of a mess of the internal implementation, though, with
`asg_mut()` sprinkled about, so maybe the next commit can clean that up a
bit.  EDIT: After adding `AsMut` to a bunch of asg::graph::object::*
methods, I decided against it, because it messes with the inferred
ownership, requiring explicit borrows via `as_mut()` where they were not
required before.  I think the existing code is easier to reason about than
what would otherwise result from having `mut asg: impl AsMut<Asg>`
everwhere.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz fc569f7551 tamer: asg::air::tpl: Distinct, generalized root and targets
Previously, `AirTplAggregate` worked only in a `Pkg` context, being able to
root `Tpl` `Ident`s in `Pkg` and expand only into `Pkg`.  This still does
the same, but generalizes to allow for different roots and expansion
targets.

This will be utilized to parse nested templates.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz e1c8e371d5 tamer: nir::tplshort: Desugar nested template applications
I'm happy with how this ended up turning out---I was able to accomplish this
without having to introduce any additional state to the parser (I _removed_
a state, actually) by tweaking NIR a bit in a previous commit.

We can't update the system test yet, though, because nested templates are
not yet supported by asg::air::tpl; that'll come next.  If you try, you'll
be greeted with this error presently (which is worth showing since you'll
never see it unless you're hacking TAMER):

,=====[ ./tests/xmli/template/ logs ]======
|
| thread 'main' panicked at 'not yet implemented: internal error:
| note: nested tpl open
|    --> ./tests/xmli/template/src.xml:129:5
|     |
| 129 |     <t:inner-short />
|     |     -------------- note: for this template
|
|
| !!! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !!!
| !!!        THIS IS AN UNFINISHED FEATURE IN TAMER         !!!
| !!! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !!!
| !!! This message means that TAMER has encountered an      !!!
| !!! unrecoverable error that forced it to terminate       !!!
| !!! processing.                                           !!!
| !!!                                                       !!!
| !!! TAMER has attempted to provide you with contextual    !!!
| !!! information above that might allow you to work around !!!
| !!! this problem until it can be fixed.                   !!!
| !!!                                                       !!!
| !!! Please report this error, including the above         !!!
| !!! diagnostic output beginning with 'internal error:'.   !!!
| !!! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ !!!
| ', src/asg/air/tpl.rs:207:55
| note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
| Command exited with non-zero status 101
| 0/165fault 0/8io 3528rss 14/2ctx
| /home/[...]/tame/tamer/target/debug/tamec -o ./tests/xmli/template/out.xmli --emit xmlo ./tests/xmli/template/src.xml
|
`====[ end ./tests/xmli/template/ logs ]====

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz 6581c9946c tamer: nir::air: Remove Nir and NirEntity enum prefixes from variants
This is a long-overdue change to make this easier to read, but I'm _still_
holding off on refactoring, since there's still a lot of room for different
patterns to form with all of NIR that is left.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz e595698309 tamer: nir: Apply*Short variants
This adds explicit variants for shorthand template application.  This is
less cryptic, and we'll be able to check for the close directly during
desugaring.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz 975f60bff9 tamer: nir::tplshort: Desugar body into @values@
This represents a significant departure from how the XSLT-based TAME handles
the `@values@` param, but it will end up having the same effect.  It builds
upon prior work, utilizing the fact that referencing a template in TAMER
will expand it.

The problem is this: allowing trees in `Meta` would add yet another
container; we have `Pkg` and `Tpl` already.  This was the same problem with
template application---I didn't want to add support for binding arguments
separately, and so re-used templates themselves, reaching the generalization
I just mentioned above.

`Meta` is intended to be a lexical metasyntatic variable.  That keeps its
implementation quite simple.  But if we start allowing trees, that gets
rather complicated really quickly, and starts to require much more complex
AIR parser state.

But we can accomplish the same behavior by desugaring into an existing
container---a template---and placing the body within it.  Then, in the
future, we'll parse `param-copy` into a simple `Air::RefIdent`, which will
expand the closed template and produce the same result as it does today in
the XSLT-based system.

This leaves open issues of closure (variable binding) in complex scenarios,
such as in templates that introduce metavariables to be utilized by the
body.  That's never a practice I liked, but we'll see how things evolve.

Further, this does not yet handle nested template applications.

But this saved me a ton of work.  Desugaring is much simpler.

The question is going to be how the XSLT-based compiler responds to this for
large packages with thousands of template applications.  I'll have to see
if it's worth the hit at that time, or if we should inline it when
generating the `xmli` file, producing the same `@values@` as
before.  But as it stands at this moment, the output is _not_ compatible
with the current compiler, as it expects `@values@` to be a tree, so a
modification would have to be made there.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz 120f5bdfef tamer: nir::tplshort: Remove variant enum prefixes
This just cleans up a little before I introduce more code, making this
easier to read.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz 9c0e20e58c tamer: asg: Shorthand and long-form template arguments
This applies to template application only; there's still some work to do for
template parameters in definitions (well, for deriving them in `xmli` at
least).  And, as you can see, there's still a lot of TODO items here.

I ended up backtracking on tree edges to Meta, and even on cross edges to
Meta, because it complicated xmli derivation with no benefit right now;
maybe a cross edge will be re-added in the future, but I need to move on and
see where this takes me.

But, it works.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz fcd25d581c tamer: asg::air::expr: Do not cache (globally) identifiers created with StoreDangling
I'm not happy with this implementation.  The linear search is undesirable,
but not too bad (and maybe wouldn't even be worth caching, if this were the
whole story), but we _also_ need to prevent duplicate identifiers.  We are
not going to want to perform a linear search of a linked list (effectively)
every time we add an identifier to check for uniqueness, so I think the
caching is going to have to be generalized very shortly anyway.

As it stands now, a duplicate identifier would cause an error at expansion
time.  That's not what we want, but it's not terrible, because you can have
that same problem in normal circumstances without local conflicts.

But this'll be used for metavariables as well, where we absolutely _do_ want
to fail at template definition time.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz 1c7df894ea tamer: asg::graph: *lookup{=>_global}*
Identifier lookups, as done using the graph methods today, look up from a
cache representing the global environment.

Templates must not contribute to this environment until expansion.  Further,
metavariables will not be present in this environment.  To avoid confusion
and help obviate accidental contributions to this environment, the methods
have been renamed.  This will also allow for the creation of more general
methods down the line.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz 25121c1086 tamer: asg::air: Test formatting (token nesting)
This makes the tests quite a bit easier to understand visually.  I've been
doing this with all new tests but had to go back to some old ones, and still
have more to go back to.  Baby steps.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz bef68e1634 tamer: nir: Desugar shorthand template params and yield AIR
I had intended for this to be a full vertical slice initially, but AIR's
parser is going to need enough work that it'll muddy this patch a bit too
much.

This keeps the desugaring simple, which is what I was hoping for.

The next step is to load it into the graph and emit regenerated longhand
sources.

I also don't like how the namespace prefix is just being ignored for
shorthand param desugaring.  This is also the case in the XSLT-based
compiler, but this violates TAMER's principle that it should parse every bit
of information; nothing should be ignored.  If something does not contribute
useful information, then it is not a useful construct and ought to be
rejected.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz 3dcb2cb03c tamer: nir::NirEntity::TplParam: Optional name/value pair
This will be used for shorthand desugaring.

DEV-13708
2023-03-29 12:58:35 -04:00
Mike Gerwitz a686855e9d tamer: Introduce desugaring operation for shorthand template application
This moves translation from NirToAir into TplShortDesugar, and changes the
output from AIR to NIR.

This is going to be much easier to reason about as a desugaring
operation (and indeed that's always how TAME has implemented it, in XSLT);
this keeps the complexity isolated.

Ideally, NirToAir wouldn't even accept tokens that it can't handle, but
that's going to take quite a bit more work and I don't have the time right
now.  Instead, we'll fail at runtime with some hopefully-useful
information.  It shouldn't actually happen in practice.

DEV-13708
2023-03-29 12:58:34 -04:00
Mike Gerwitz 3e9f407527 tamer: asg::air::ir: Remove TplApply
The implementation decided upon in the previous commits have made this
unnecessary, using `RefIdent` to produce `Tpl->Ident[->Tpl]` instead.

DEV-13708
2023-03-29 12:58:34 -04:00
Mike Gerwitz 669302700a tamer: build-aux/asg-ontviz: Vary arrowhead for cross edges
This makes it more visually apparent, when looking directly at a node,
whether an edge could represent a tree edge.

Dynamic edges could be tree edges, so I left those solid; that's the more
important visual indicator that I'm interested in, and it's disambiguated by
the dashed line.

DEV-13708
2023-03-29 12:58:34 -04:00
Mike Gerwitz 893da0ed20 tamer: asg: Dynamically determined cross edges
Previous to this commit, ontological cross edges were declared
statically.  But this doesn't fare well with the decided implementation for
template application.

The documentation details it, but we have Tpl->Ident which could mean "I
define this Ident once expanded", or it could mean "this is a reference to a
template I will be applying".  The former is a tree edge, the latter is a
cross edge, and that determination can only be made by inspecting edge data
at runtime.

It could have been resolved by introducing new Object types, but that is a
lot of work for little benefit, especially given that only (right now) the
visitor uses this information.

DEV-13708
2023-03-29 12:58:34 -04:00
Mike Gerwitz e132f108e8 tamer: asg::air: {=>diagnostic_}todo!
I forgot about my `diagnostic_todo!` macro!  The purpose was to help guide
development by obviating what comes next in test failures.

DEV-13708
2023-03-29 12:58:34 -04:00
Mike Gerwitz 9d50157f8e tamer: Very basic support for template application NIR -> xmli
This this a big change that's difficult to break up, and I don't have the
energy after it.

This introduces nullary template application, short- and long-form.  Note
that a body of the short form is a `@values@` argument, so that's not
supported yet.

This continues to formalize the idea of what "template application" and
"template expansion" mean in TAMER.  It makes a separate `TplApply`
unnecessary, because now application is simply a reference to a
template.  Expansion and application are one and the same: when a template
expands, it'll re-bind metavariables to the parent context.  So in a
template context, this amounts to application.

But applying a closed template will have nothing to bind, and so is
equivalent to expansion.  And since `Meta` objects are not valid outside of
a `Tpl` context, applying a non-closed template outside of another template
will be invalid.

So we get all of this with a single primitive (getting the "value" of a
template).

The expansion is conceptually like `,@` in Lisp, where we're splicing trees.

It's a mess in some spots, but I want to get this committed before I do a
little bit of cleanup.
2023-03-29 12:58:32 -04:00
Mike Gerwitz aa229b827c tamer: Makefile.am: cargo clippy: Use active feature flags
This was missing `@FEATURES@`, which was causing more compilation than
necessary, but also causing clippy to evaluate different code.

This also adds RUSTFLAGS, for the same reason of not wanting to recompile.

DEV-13708
2023-03-17 10:20:56 -04:00
Mike Gerwitz 03b46ebeff tamer: asg::air::tpl::TplState: Explicitly store reachability of active template
This is a small part of a larger change that I'm still working on.

DEV-13708
2023-03-16 15:08:15 -04:00
Mike Gerwitz d930b26487 tamer: asg::air::ir: Decide on TplApply and expansion
This chooses Option B, as stated would likely be the case in the previous
commit.  The reasons are practical---I intend to support partial application
if doing so is worth it, either in implementation of the compiler or the
source language.

Closed templates can be referenced using `IdentRef` to trigger
expansion---their value is what they expand into, and they are spliced into
that point in the tree, like `,@` in Lisp.  We are able to overload this
behavior because we have the necessary type information.

However, I don't want to have to generate an Ident for every single template
expansion; there are many tens of thousands of them in our production
system.  Since AIR doesn't presently have a way to deal with this situation,
I'll for now add a special token that will close and expand a template in
place; it can be replaced with two separate tokens (`TplEnd` + `Ref`, for
example) in the future if such a need arises.

Are we there yet...?

DEV-13708
2023-03-15 16:40:08 -04:00
Mike Gerwitz be81878dd7 tamer: src::asg: Scaffolding for metasyntactic variables
Also known as metavariables or template parameters.

This is a bit of a tortured excursion, trying to figure out how I want to
best represent this.  I have a number of pages of hand-written notes that
I'd like to distill over time, but the rendered graph ontology (via
`asg-ontviz`) demonstrates the broad idea.

`AirTpl::TplApply` highlights some remaining questions.  What I had _wanted_
to do is to separate the concepts of application and expansion, and support
partial application and such.  But it's going to be too much work for now,
when it isn't needed---partial application can be worked around by simply
creating new templates and duplicating params, as we do today, although that
sucks and is a maintenance issue.  But I'd rather address that head-on in
the future.

So it's looking like Option B is going to be the approach for now, with
templates being closed (as in, no free metavariables) and expanded at the
same time.  This simplifies the parser and error conditions significantly
and makes it easier to utilize anonymous templates, since it'll still be the
active context.

My intent is to get at least the graph construction sorted out---not the
actual expansion and binding yet---enough that I can use templates to
represent parts of NIR that do not have proper graph representations or
desugaring yet, so that I can spit them back out again in the `xmli` file
and incrementally handle them.  That was an option I had considered some
months ago, but didn't want to entertain it at the time because I wasn't
sure what doing so would look like; while it was an attractive approach
since it pushes existing primitives into the template system (something I've
wanted to do for years), I didn't want to potentially tank performance or
compromise the design for it after I had spent so much effort on all of this
so far.

But my efforts have yielded a system that significantly exceeds my initial
performance expectations, with a decent abstractions, and so this seems
viable.

DEV-13708
2023-03-15 16:40:07 -04:00
Mike Gerwitz 9e5958d89e tamer: asg::air::ir::Air: Open/Close => Start/End in token names
See the Air docblock for more information.  I'm introducing new tokens for
the template system, which uses the terms "free" and "closed".  I prefer
open/close for delimiters, as I've expressed elsewhere, but unfortunately it
conflicts too much (and too confusingly) with other standard terminology as
we get more into the formal side of the language.

DEV-13708
2023-03-15 10:59:25 -04:00
Mike Gerwitz 0e42788dcc tamer: asg::air: Restrict AirTplAggregate token domain to new AirTemplatable
This removes special cases, but it does complicate the parent `AirAggregate`
parser.  A pattern of delegation is forming, though abstracting it may be an
interesting challenge, given Rust's limitation on macro invocations as match
arms.  But, I think I can manage by generating the entire match using a
macro with a match-compatible syntax, augmenting where
needed...maybe.  This'll be messy.

...but if I can write the nightmare that is `ele_parse!`, I'm sure I can
manage this.  I just prefer to avoid complex macros unless I really need
them.

DEV-13708
2023-03-11 00:58:08 -05:00
Mike Gerwitz 2233c69bbf tamer: asg::graph::object: Some minor proofreading 2023-03-10 23:44:40 -05:00
Mike Gerwitz 18fa910e0f tamer: {tools=>build-aux}/asg-ontviz
Now that these are actually intended to be used as part of the build, this
is a more appropriate location.  I originally wrote it as a manual tool.

DEV-13708
2023-03-10 15:13:30 -05:00
Mike Gerwitz a5b03e8790 tamer: Embed ASG ontology visualization in rustdoc-generated docs
There, in-your-face and not hidden in some tools directory.

DEV-13708
2023-03-10 14:28:00 -05:00
Mike Gerwitz f733a85597 tamer: tools/asg-ontviz: ASG ontology visualization
This parses the declarative `object_rel!` definitions from the Rust sources
and produces a DOT representation of the ontology of the graph, which can
then be rendered using Graphviz.

This does not yet introduce it into the build; it ought to be run as part of
`make check` (without rendering with Graphviz) to ensure that we catch
breaking changes, and `make html` ought to integrate it into the
documentation, perhaps as part of `asg::graph` or `asg::graph::object`.

DEV-13708
2023-03-10 14:28:00 -05:00
Mike Gerwitz 0aa69c079d tamer: NIR->xmli: Ceil, Floor expressions
Small break from templates for something easier.  I have COVID-19, so I'll
use that as my excuse for wanting to be more lazy.

The real reason is to see some more concrete progress and ensure that
patterns hold for simple expressions before further refactoring.

But, before I proceed with such refactoring, I really ought to approach
something that requires a NIR desugaring step, like case statements.

DEV-13708
2023-03-10 14:28:00 -05:00
Mike Gerwitz b9f0fada51 tamer: asg::graph::object::expr::ExprOp: Doc comment fix {//=>///}
DEV-13708
2023-03-10 14:28:00 -05:00
Mike Gerwitz e6325c4c1d tamer: tests/xmli: Estimate tamec time in milliseconds
Going higher than that doesn't make sense because we're in shell and
invoking commands all around this, so even milliseconds isn't going to be
entirely accurate here.  However, what I am more interested in is observing
time relative to other runs; this isn't intended for profiling, but for
eyeballing unexpected behavior.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz b84ee356d5 tamer: tests/xmli: Formatted and more informative output
There's a lot to look at, especially in the event of failure.  Further, I
wanted to add additional statistics that could be eyeballed.

Right now, tamec is too fast (at least on my machine) for the precision of
/usr/bin/time: we need milliseconds, but we only get hundredths of a
second.  So it'll all show as 0:00.00s.  Which is okay, for now; it just
shouldn't exceed that. ;)

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz a261e75fe0 tamer: tests/xmli: Break apart single test case
This would have gotten unwieldy as time goes on, and already made looking at
traces very difficult.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 7ebd494752 tamer: tests/xmli/expected.xml: Align with src
This just makes this easier to compare side-by-side.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 343f5b34b3 tamer: asg::air: Template support for dangling expressions
The intent was to have a very simple implementation of `hold_dangling` and
have everything work.  But, I had a nasty surprise when the system tests
caught bug caused by some interesting depth interactions as it relates to
`xmli` and auto-closing.

I added an extra test/example in `asg::graph::visit::test` to illustrate the
situation; it was difficult to derive from the traces, but trivially obvious
once I wrote it out as an example.

With that, templates can now aggregate tokens for dangling expressions.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 286f4cb679 tamer: tests/xmli: Reduce output on failure
This won't try the fixpoint test if the prior one fails, which will always
cause that one to fail.  And it further won't attempt the diff on
compilation failure.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 5c60c5fd15 tamer: asg::air::tpl: Parse template body expressions
And finally we have tokens aggregated onto the ASG in the context of a
template.  I expected to arrive here much more quickly, but there was a lot
of necessary refactoring.  There's a lot more that could be done, but I need
to continue; I had wanted this done a week ago.

It is worth noting, though, that this finally achieves something I had been
wondering about since the inception of this project---how I'd represent
templates on the graph.  I think this worked out rather nicely.  It wasn't
even until a few months ago that I decided to use AIR instead of NIR for
that purpose (NIR wouldn't have worked).

And note how I didn't have to touch the program derivation at all---the
system test just works with the AIR change, because of the consistent
construction of the graph.  Beautiful.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 431df6cecb tamer: asg::air::expr: Dead states for AirBind
This hoists the errors back into `AirAggregate`; I need dead states for the
`AirTplAggregate` parser so that it will know when to (and not to) interpret
tokens in the context of the template itself.

In a previous commit message, I had pondered whether it may be possible to
eliminate the dead state transition, and yet here I've used it with both of
the sub-parsers now.  So it seems like the better option in the future may
be to narrow the type further---to say precisely _what_ types of tokens may
yield a dead state transition; otherwise you lose the match information from
the parser that yielded it.

A stubbornly persistent problem in Rust, this magical and hidden match
knowledge.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 1770949b9a tamer: asg::air::expr: Move Dangling expression handling into RootStrategy
And with this, hopefully we are now finally prepared for dangling
expressions in templates.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 231296d003 tamer: asg::air::expr: Introduce RootStrategy
This sets us up to be able to determine how `Dangling` expressions will be
rooted into templates.

This new strategy isn't yet handling `Dangling`; I wanted to get this
committed first so that the `Dangling` refactoring is more clear.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz fc1d55c4c5 tamer: asg::air::expr: Generic target ObjectKind
Expressions were previously tied to packages.  This prepares for using a
`Tpl` as a container for expressions.

This does not yet handle the situation of auto-rooting dangling expressions
within the container.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 266c9eb05a tamer: parse::state::ParseState: Remove `Eq` derivation
This is unneeded and is just a pain.  If ever we need `Eq`, it could be
implemented only for `ParseState`s that actually need it.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 8cb781ccca tamer: asg::air::expr::ExprStack: {SPair=>ObjectIndex} reachable evidence
This result in less useful debug output, but it'll be needed for using
a (possibly-anonymous) template as evidence.

This evidence is simply for debugging, and to require some sort of value
during development to help obviate when maybe something is being done
incorrectly (if no obvious value exists).

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz c1d04f1cf4 tamer: asg::air: Extract template parsing into `tpl`
Same as the previous commit.  These commits have significantly reduced the
cognitive burden of working on this subsystem.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 4fd8e9ea40 tamer: asg::air: Extract expression parsing into `expr`
This is more of the same refactoring that has been happening.  This
extraction also helps emphasize the relationship between imported objects,
and isolates the growing number of test cases.  This parser will only grow.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz f307f2d70b tamer: asg::air: Extract template parsing into own parser
Just as was done with the expression parser, which this will utilize.  This
initializes it, but doesn't yet make use of it (`AirExprAggregate`).

Refactoring was definitely needed; decomposing this is quite a bit of work,
in no small part because of the complexity.  This helps significantly.

DEV-13708
2023-03-10 14:27:59 -05:00
Mike Gerwitz 25c0aa180e parse::state::transition::TransitionResult::branch_dead: Add branch context
This works around limitations of Rust's borrow checker as of the time of
writing.  See the provided documentation for more information.

The branch context is not yet exposed to the `delegate` family of methods;
it will be added only as needed in the future.

DEV-13708
2023-03-10 14:27:59 -05:00