Commit graph

10 commits

Author SHA1 Message Date
Emily Toop
f7285b268b Rebase against rust branch. 2017-04-07 13:21:09 +01:00
Nick Alexander
5369f03464 Improve parsing of nested edn::ValueAndSpan streams. r=rnewman (#393)
* Pre: Expose more in edn.

* Pre: Make it easier to work with ValueAndSpan.

with_spans() is a temporary hack, needed only because I don't care to
parse the bootstrap assertions from text right now.

* Part 1a: Add `value_and_span` for parsing nested `edn::ValueAndSpan` instances.

I wasn't able to abstract over `edn::Value` and `edn::ValueAndSpan`;
there are multiple obstacles.  I chose to roll with
`edn::ValueAndSpan` since it exposes the additional span information
that we will want to form good error messages in the future.

* Part 1b: Add keyword_map() parsing an `edn::Value::Vector` into an `edn::Value::map`.

* Part 1c: Add `Log`/`.log(...)` for logging parser progress.

This is a terrible hack, but it sure helps to debug complicated nested
parsers.  I don't even know what a principled approach would look
like; since our parser combinators are so frequently expressed in
code, it's hard to imagine a data-driven interpreter that can help
debug things.

* Part 2: Use `value_and_span` apparatus in tx-parser/.

I break an abstraction boundary by returning a value column
`edn::ValueAndSpan` rather than just an `edn::Value`.  That is, the
transaction processor shouldn't care where the `edn::Value` it is
processing arose -- even we care to track that information we should
bake it into the `Entity` type.  We do this because we need to
dynamically parse the value column to support nested maps, and parsing
requires a full `edn::ValueAndSpan`.  Alternately, we could cheat and
fake the spans when parsing nested maps, but that's potentially
expensive.

* Part 3: Use `value_and_span` apparatus in query-parser/.

* Part 4: Use `value_and_span` apparatus in root crate.

* Review comment: Make Span and SpanPosition Copy.

* Review comment: nits.

* Review comment: Make `or` be `or_exactly`.

I baked the eof checking directly into the parser, rather than using
the skip and eof parsers.  I also took the time to restore some tests
that were mistakenly commented out.

* Review comment: Extract and use def_matches_* macros.

* Review comment: .map() as late as possible.
2017-04-06 10:06:28 -07:00
Nick Alexander
4b874deae1 Lookup refs, nested vector values, map notation. Fixes #180, fixes #183, fixes #284. (#382) r=rnewman
* Pre: Fix error in parser macros.

* Pre: Make test unwrapping more verbose.

* Pre: Make lookup refs be (lookup-ref a v) in the entity position.

This has the advantage of being explicit in all situations and
unambiguous at parse-time.  This choice agrees with the Clojure
implementation but not with Datomic.  Datomic treats [a v] as a lookup
ref, is ambiguous at parse-time, and is disambiguated in ways I do not
understand at transaction time.  We mooted making lookup refs [[a v]]
and outlawing nested value vectors in transactions, but after
implementing that approach I decided it was better to handle lookup
refs at parse time and therefore outlawing nested value vectors is not
necessary.

* Handle lookup refs in the entity and value columns. Fixes #183.

* Pre 0a: Use a stack instead of into_iter.

* Pre 0b: Dedent.

* Pre 0c: Handle `e` after `v`.

This allows to use the original `e` while handling `v`.

* Explode value lists for :db.cardinality/many attributes. Fixes #284.

* Parse and accept map notation. Fixes #180.

* Pre: Modernize add() and retract() into one add_or_retract().

* Pre: Add is_collection and is_atom to edn::Value.

* Pre: Differentiate atoms from lookup-refs in value position.

Initially, I expected to accept arbitrary edn::Value instances in the
value position, and to differentiate in the transactor.  However, the
implementation quickly became a two-stage parser, since we always
wanted to parse the resulting value position into some other known
thing using the tx-parser.  To save calls into the parser and to allow
the parser to move forward with a smaller API surface, I push as much
of this parsing as possible into the initial parse.

* Pre: Modernize entities().

* Pre: Quote edn::Value::Text in Display.

* Review comment: Add and use edn::Value::into_atom.

* Review comment: Use skip(eof()) throughout.

* Review comment: VecDeque instead of Vec.

* Review comment: Part 0: Rename TempId to TempIdHandle.

* Review comment: Part 1: Differentiate internal and external tempids.

This breaks an abstraction boundary by pushing the Internal/External
split up to the Entity level in tx/ and tx-parser/.  This just makes
it easier to explode Entity map notation instances into Entity
instances, taking an existing External tempid :db/id or generating a
new Internal tempid as appropriate.  To do this without breaking the
abstraction boundary would require adding flexibility to the
transaction processor: we'd need to be able to turn Entity instances
into some internal enum and handle the two cases independently.  It
wouldn't be too hard, but this reduces the combinatorial type
explosion.
2017-03-27 16:30:04 -07:00
Nick Alexander
dcd9bcb1ce Extract partial storage abstraction; use error-chain throughout. Fixes #328. r=rnewman (#341)
* Pre: Drop unneeded tx0 from search results.

* Pre: Don't require a schema in some of the DB code.

The idea is to separate the transaction applying code, which is
schema-aware, from the concrete storage code, which is just concerned
with getting bits onto disk.

* Pre: Only reference Schema, not DB, in debug module.

This is part of a larger separation of the volatile PartitionMap,
which is modified every transaction, from the stable Schema, which is
infrequently modified.

* Pre: Fix indentation.

* Extract part of DB to new SchemaTypeChecking trait.

* Extract part of DB to new PartitionMapping trait.

* Pre: Don't expect :db.part/tx partition to advance when tx fails.

This fails right now, because we allocate tx IDs even when we shouldn't.

* Sketch a db interface without DB.

* Add ValueParseError; use error-chain in tx-parser.

This can be simplified when
https://github.com/Marwes/combine/issues/86 makes it to a published
release, but this unblocks us for now.  This converts the `combine`
error type `ParseError<&'a [edn::Value]>` to a type with owned
`Vec<edn::Value>` collections, re-using `edn::Value::Vector` for
making them `Display`.

* Pre: Accept Borrow<Schema> instead of just &Schema in debug module.

This makes it easy to use Rc<Schema> or Arc<Schema> without inserting
&* sigils throughout the code.

* Use error-chain in query-parser.

There are a few things to point out here:

- the fine grained error types have been flattened into one crate-wide
  error type; it's pretty easy to regain the granularity as needed.

- edn::ParseError is automatically lifted to
  mentat_query_parser::errors::Error;

- we use mentat_parser_utils::ValueParser to maintain parsing error
  information from `combine`.

* Patch up top-level.

* Review comment: Only `borrow()` once.
2017-02-24 15:33:48 -08:00
Richard Newman
a10f68fdb7 Mark every project as being part of the workspace. r=nalexander
This allows `cargo test --all` to work.
2017-02-20 11:04:08 -08:00
Joe Walker
f591c90738 Use mentat-parser-utils in tx-parser. Fixes #235; r=rnewman,victorporof
Move macros query-parser/…/parser_utils.rs → parser-utils/…/query.rs

Signed-off-by: Joe Walker <jwalker@mozilla.com>
2017-02-10 18:30:03 +00:00
Richard Newman
cd5f0d642c Doc comment for ResultParser. 2017-02-02 15:23:24 -08:00
Richard Newman
5d74f1ee94 Add utilities for defining parsers. (#218) r=vporof
satisfy_unwrap and ResultParser go into mentat_parser_utils.
2017-02-02 10:25:05 -08:00
Richard Newman
fcdf759399 Rename parser_utils to mentat_parser_utils, clean up imports. (#234) r=vporof 2017-02-02 08:18:04 -08:00
Victor Porof
ba1896b684 Extract assert_parses_to into a parser utility crate, r=rnewman. Fixes #200
Signed-off-by: Victor Porof <vporof@mozilla.com>
2017-02-02 10:17:08 +01:00