This is again a step closer to the book, but there are some notable
differences:
* Only constants encountered by the compiler are interned, all other
string operations (well, concatenation) happen with heap objects.
* OpReturn will always ensure that a returned string value is newly
heap allocated and does not reference the interner.
Change-Id: If4f04309446e01b8ff2db51094e9710d465dbc50
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2582
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
This is based on this matklad post:
https://matklad.github.io/2020/03/22/fast-simple-rust-interner.html
It's modified slightly to provide a safer interface and slightly more
readable implementation:
* interned string IDs are wrapped in a newtype that is not publicly
constructible
* unsafe block is reduced to only the small scope in which it is
needed
* lookup lifetime is pinned explicitly to make the intent clearer when
reading this code
Change-Id: Ia3dae988f33f8e5e7d8dc0c1a9216914a945b036
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2578
Tested-by: BuildkiteCI
Reviewed-by: tazjin <mail@tazj.in>
Adds support for true, false & nil. These each come with a new
separate opcode and are pushed directly on the stack.
Change-Id: I405b5b09496dcf99d514d3411c083e0834377167
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2571
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
If I was adding any dependencies, this might be a good one for a
property-based test thing, but I'm not going to.
Change-Id: Ia801d041479d1a88c59ef9e0fe1460b3640382e3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2569
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
This lets us suppress reporting of additional errors from the compiler
until a synchronisation point is reached.
Change-Id: Iacf90949f868fbdb4349750065b5e458cf74d32a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2557
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
This one necessarily has to diverge more from the book than the
treewalk interpreter did, so some of this is expected to change, but
I'm happy with the rough shape.
Since we're reusing the old scanner, the compiler/parser struct owns
an iterator over all tokens with which the pull-scanner from the
bytecode chapters is simulated.
Change-Id: Icfa0bd4729d9df786e08f7e49a25cba1b9989a91
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2556
Tested-by: BuildkiteCI
Reviewed-by: tazjin <mail@tazj.in>
This is significantly simplified from the version in the book, since
I'm using Rust's Vec and not implementing dynamic arrays manually.
We'll see if I run into issues with that ...
Change-Id: Ie3446ac3884b850f3ba73a4b1a6ca14e68054188
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2413
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
Right now this introduces a simple mechanism to flip between the
interpreters.
Change-Id: I92ee920c53d76ab6b664ac671993a6d6426af61a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2412
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
