plum

#treesitter#compiler#wasm

git clone https://git.pyrossh.dev/plum

A statically typed, imperative programming language inspired by rust, python

04de243 — Peter John 2026-11-06T10:57:29+05:30 
plans: FBIP stage 1, keep the chain
Files changed (1) hide show
  1. docs/plans/2026-11-06-fbip-stage1.md +3 -3
docs/plans/2026-11-06-fbip-stage1.md CHANGED
@@ -75,8 +75,8 @@ e.g. `v = v.bumped()` in a `for` loop, with `bumped(self) = Cell(..self, n: self
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  **LOC owned:** 180
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  **Tests:** fast
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  **Consumes:** the proof covers method `self` and typed receivers, including overrides, `x = x.m(..)` hand-over in loops and fields, and functions that return their unique argument; `tests/fbip/` holds aliasing tests (T3)
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- **Produces:** `Array.with(self, i, v) -> Array[T]` returns the array with one element changed, in place when the receiver is proved unique and through a copy otherwise, with no cost for the check at runtime
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- e.g. `Array.with`: `a = a.with(i, i * 2)` in a loop on a fresh array allocates nothing per step, shown by `--explain-fusion` and a byte-count or allocation test
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+ **Produces:** `Array.with` returns the array with one element changed, in place when the receiver is proved unique and through a copy otherwise, with no cost for the check at runtime
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+ e.g. in a loop on a fresh array, `a = a.with(i, i * 2)` allocates nothing per step, shown by `--explain-fusion` and a byte-count or allocation test
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  **Notes:** Works for flat-struct element arrays too: `Array[Vec2]` is stored field by field. A proved site compiles exactly like `Array.set`. Out-of-range behaves as `set` does.
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  **Test code:** aliasing tests for arrays: alias then `with`, the original is unchanged; array in a struct field; array returned from a helper; `Array[Vec2]`. An `opsOf`-style wasm test that a proved site has no `array.copy`, and an unproved one does.
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@@ -85,7 +85,7 @@ e.g. `Array.with`: `a = a.with(i, i * 2)` in a loop on a fresh array allocates n
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  **Components:** 2
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  **LOC owned:** 150
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  **Tests:** fast
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- **Consumes:** `Array.with(self, i, v) -> Array[T]` returns the array with one element changed, in place when the receiver is proved unique and through a copy otherwise, with no cost for the check at runtime (T4)
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+ **Consumes:** `Array.with` returns the array with one element changed, in place when the receiver is proved unique and through a copy otherwise, with no cost for the check at runtime (T4)
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  **Produces:** `fip fun` is a compile error, at the exact spot and giving the reason, when a spread or `Array.with` in that function isn't proved in place
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  e.g. `fip fun f(a: Array[Int]) -> Array[Int] = { b := a; a.with(0, 1) }` errors at `a.with`, saying `a` is also held by `b`
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  **Notes:** Check at the end of the pipeline, because the proof runs after fusion: the error comes from the driver with the node's span. Under `--no-fbip` or `--no-fusion`, `fip` isn't enforced, and say so. Calls from a `fip fun` to other functions aren't required to be `fip`, so it's a local check. Formatter (`format.scm`) and LSP keyword completion learn the keyword.