Commit graph

29 commits

Author SHA1 Message Date
Vincent Ambo
26ed836e1d feat(tazjin/rlox): Add support for scoped environments
Adds scoped environments using a sophisticated structure known as an
SRPT, which stands for "shitty parent pointer tree".

Change-Id: I62f66aabe6eb32ea01c4cabcca5b03cfefcc28ee
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2301
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-31 15:33:08 +00:00
Vincent Ambo
48a54625ce refactor(tazjin/rlox): Separate assignment and definition
So that:

> var a = 15;
> b = 12;
Error in program: Error { line: 0, kind: UndefinedVariable("b") }
> a = 12; print a;
Number(12.0)

Change-Id: I687e95ccc2d3084e39a71bd452656ae981c95191
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2300
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-31 14:32:03 +00:00
Vincent Ambo
cc958e6730 feat(tazjin/rlox): Implement mutable variable assignment
Change-Id: I56db10a5ac26958ae27a8d4c8fa7b8f8285bc7e1
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2299
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-31 14:32:03 +00:00
Vincent Ambo
8ab66f1689 refactor(tazjin/rlox): Retain interpreter state in REPL
Change-Id: Id60760e241ad0e45871b48e499f58e9831d57316
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2298
Tested-by: BuildkiteCI
Reviewed-by: tazjin <mail@tazj.in>
2020-12-31 11:19:42 +00:00
Vincent Ambo
78355d3c0b feat(tazjin/rlox): Add global variable support in interpreter
Change-Id: I4134cf78dc3934a517ad0c848ae1d3729abaf882
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2297
Tested-by: BuildkiteCI
Reviewed-by: tazjin <mail@tazj.in>
2020-12-31 11:19:42 +00:00
Vincent Ambo
0f9a7b3f86 feat(tazjin/rlox): Parse variable assignment & access
Change-Id: I9894d76716d739e85a4757d9e658f884228e7f52
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2290
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-22 20:18:01 +00:00
Vincent Ambo
a104afa6ea refactor(tazjin/rlox): Introduce declarations in parser
Change-Id: I873fdd53319ec36da18926d9477e809a69dbace7
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2288
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-22 10:13:28 +00:00
Vincent Ambo
75ae25daa9 feat(tazjin/rlox): Add support for statements
First part of
https://craftinginterpreters.com/statements-and-state.html

Supports print statements, as well as evaluation for the sake of
it (i.e. future side-effects).

Change-Id: Ic6653b568f98d6cfe3f297615b7113c0ba1d9a70
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2287
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-22 10:13:28 +00:00
Vincent Ambo
5ebe28cca2 feat(tazjin/rlox): Add runtime type error handling
Change-Id: I0d52bc9ff5be6421cb4131265ed28ce1ea7d8ff3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2282
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-20 16:25:54 +00:00
Vincent Ambo
bc6775c318 feat(tazjin/rlox): Implement tree-walk interpreter of exprs
This is only a subset of the Lox spec so far. It implements the
language up to the runtime error chapter on
https://craftinginterpreters.com/evaluating-expressions.html

Change-Id: I295dbf4b6544420d6fe80b6aaba661fb21acdea6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2281
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-20 16:25:54 +00:00
Vincent Ambo
42405bfa24 feat(tazjin/rlox): Synchronise parser state after errors
This lets the parser collect multiple errors instead of returning
after the first one, with some optimistic synchronisation after
encountering something that looks wonky.

Change-Id: Ie9d0ce8de9dcc7a3d1e7aa2abe15f74cab0ab96b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2236
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-06 17:34:57 +00:00
Vincent Ambo
1835b2be99 feat(tazjin/rlox): Wire up parser to the REPL
Change-Id: I940448c63ce105d53a0f281b6320ffb01378f207
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2235
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-06 14:58:39 +00:00
Vincent Ambo
4812fc2ee6 feat(tazjin/rlox): Implement parsing of parenthesised expressions
Change-Id: I0e6bd71fd787b719104ef93fc52df4090dc415b9
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2234
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-06 14:30:59 +00:00
Vincent Ambo
28002fcea5 refactor(tazjin/rlox): Add error plumbing in parser functions
Change-Id: I7ae3d721f76d8d69043f5ed077abbc70a18cbd92
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2233
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-06 14:30:59 +00:00
Vincent Ambo
5fcff11eae feat(tazjin/rlox): Implement parsing up to unary expressions
... with the exception of parenthesised expressions, because error
threading is not implemented yet.

Change-Id: I8d455d85e647548d5b71cbfd3d078f4970dab7fb
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2232
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-12-06 14:30:59 +00:00
Vincent Ambo
349583d5a9 feat(tazjin/rlox): Bootstrap recursive-descent parser for Lox
... mostly some AST boilerplate and a first top-level rule, plus
boilerplate similar to that set up in the Scanner.

Change-Id: I605d1de23c47a3b3702ab4f62cd3371bc3988c7d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2194
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-30 16:42:17 +00:00
Vincent Ambo
36cf7bef24 refactor(tazjin/rlox): Thread through scanner errors
... and show them to users, very crudely.

Change-Id: If4491b14db1124313f6ab7e5fbfdce9fea501d11
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2193
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-28 17:26:58 +00:00
Vincent Ambo
af793325c0 feat(tazjin/rlox): Scan identifiers and keywords
Change-Id: Ifec627605c23c25f199d47eaa91e441ed9590208
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2192
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-28 16:55:25 +00:00
Vincent Ambo
97505eb1e1 feat(tazjin/rlox): Implement number scanning
Change-Id: Ide0126d1c2274d56903092816ff9cd531c03f513
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2191
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-28 16:55:25 +00:00
Vincent Ambo
47aa92b87d feat(tazjin/rlox): Implement string scanning
Note that Lox does not support escapes, and I don't care about that.

Change-Id: Ie848cbc1164c4b005b15e29aad8fe723aaa68d1b
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2190
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-28 16:33:32 +00:00
Vincent Ambo
800d2ccde8 fix(tazjin/rlox): Clear previous line in REPL mode
Change-Id: I8acc5b0d07b2c656f9bba76a6ddac6b9088ea563
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2189
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-28 16:33:32 +00:00
Vincent Ambo
4277d3e6b4 feat(tazjin/rlox): Handle whitespace in scanner
Change-Id: Iead3efa6aa797af5c5b57c67226205bf7e39e647
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2188
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-28 16:33:32 +00:00
Vincent Ambo
9f61579dde feat(tazjin/rlox): Scan single-line comments
Change-Id: I2efafdb1374ac2863a1f8d8a9310123a7dec0900
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2187
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-28 16:33:32 +00:00
Vincent Ambo
46c6906aaa chore(tazjin/rlox): Wire scanner to interpreter to reduce warnings
... they're just noisy at the moment. This isn't complete because it
doesn't thread through scanner errors.

Change-Id: I0f75d2b20fa3f57be1af5d1d8aa8059856855825
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2162
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-27 17:29:04 +00:00
Vincent Ambo
3f6b88bce2 feat(tazjin/rlox): Implement multi-character scanning
Change-Id: Ic5a246a7f5834477aeb97824fa30ba74a8422bc1
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2161
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-27 17:29:04 +00:00
Vincent Ambo
6363efbebf refactor(tazjin/rlox): Use &[char] instead of &str in scanner
This makes it easier to work with the Unicode issue. The original
string representation can be discarded.

Change-Id: I740be4cb9654679ea7950f3899c5c709b1e7a739
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2160
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-27 17:29:04 +00:00
Vincent Ambo
3d1b116f7f feat(tazjin/rlox): Implement single-character scanning
... still not that interesting, but at this point slightly divergent
from the book:

The book embraces mutability for interpreter state, initially for
tracking whether an error condition has occured.

I avoid this by instead defining an error type and collecting the
error values, to be handled later on.

Notes: So far nothing special, but this is just the beginning of the
book. I like the style it is written in and it has pointed to some
interesting resources, such as a 1965 paper titled "The Next 700
Languages".

Change-Id: I030b38438fec9eb55372bf547af225138908230a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2144
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-23 01:15:57 +00:00
Vincent Ambo
9d2b001c4c feat(tazjin/rlox): Add basic program structure
... as well as a Nix derivation, because why not.

Change-Id: Iaf2591ab72676fe0732c3f807b3aa0cff13fb4ef
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2143
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-23 01:15:57 +00:00
Vincent Ambo
0618ff11cc feat(tazjin/rlox): Bootstrap program
This is going to be the first of two interpreters from "Crafting
Interpreters".

Change-Id: I354ddd2357444648d0245f35d92176dd176525d8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2142
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
2020-11-23 01:15:57 +00:00