feat(stdlib): add list get? and unwrap_or 🎁#167
Merged
Conversation
timfennis
force-pushed
the
feature/list-get-unwrap-or
branch
from
67096aa to
47eeb98
Compare
![chatgpt-codex-connector[bot]](https://avatars.githubusercontent.com/in/1144995?s=60&v=4){kind=small}
There was a problem hiding this comment.
💡 Codex Review
Here are some automated review suggestions for this pull request.
Reviewed commit: 67096aabba
ℹ️ About Codex in GitHub
Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you
- Open a pull request for review
- Mark a draft as ready
- Comment "@codex review".
If Codex has suggestions, it will comment; otherwise it will react with 👍.
Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
timfennis
force-pushed
the
feature/list-get-unwrap-or
branch
from
47eeb98 to
9bb43ee
Compare
timfennis
changed the title
timfennis
changed the title
timfennis
added a commit
that referenced
this pull request
Jun 2, 2026
## Context Follow-up to #167, which added `list.get?`. A Codex review of that PR found `get?` crashed on large indices: it took an `i64`, and the `#[function]` macro's integer extractor rejects `BigInt` values *before* the function body runs — even though a `BigInt` has static type `Int` and passes call resolution. So `[1].get?(10^40)` raised `arg 1: expected int, got object` instead of behaving like the advertised safe lookup. Fixing that cleanly meant settling how list element access should work in general, which is now a 2×2 matrix. ## Element accessors | function | index argument | negative index | out of bounds | |----------|----------------|----------------|---------------| | `get` | `usize` | error | error | | `get?` | `usize` | error | `None` | | `index` | `BigInt` | wraps from end | error | | `index?` | `BigInt` | wraps from end | `None` | The argument type decides negative handling: `get`/`get?` take a `usize`, so a negative index is a conversion error; `index`/`index?` take a signed `BigInt` and wrap from the end like the `[]` operator. The `?` suffix decides out-of-bounds handling (error vs `None`). `index` is the named form of `[]`; `index?` is its non-throwing twin (there is no `[]?`). ## Primary changes - **`ndc_macros/src/vm_convert.rs`** — the `usize` argument extractor now converts via `to_number()` + `TryFrom<Number> for usize`, accepting both `Int` and `BigInt` and raising a clear error on negative/oversized values. This is what lets `get`/`get?` reject negatives at the conversion layer, and it fixes the `BigInt` crash. It also fixes a latent bug: the old `*i as usize` silently wrapped a negative index to a huge `usize` for **every** `usize` builtin (`insert`, `truncate`, …). - **`ndc_stdlib/src/list.rs`** — adds `get`, `index`, `index?` and reworks `get?` onto the `usize` signature, plus a small `wrap_index` helper for the signed variants. - **`ndc_core/src/num.rs`** — clearer `NumberToUsizeError` messages (the old `BigInt` one leaked internal conversion jargon). - **Docs** — `option.md` and `list.md` document the four accessors. - **Tests** — `601_stdlib_list/004`–`012` cover the success and error paths, including the previously-crashing `get?(-1)` and `get?(10^40)`. ## Notes for reviewers - The `usize`-extractor change is the widest-reaching part: it affects all `usize` builtins, so error messages for bad size/index arguments changed. The full test suite passes (427 tests). - `index`/`index?` are list-only element access (no range/slice support); the `[]` operator still owns slicing and other container types. - <!-- Reviewer: happy with `get`/`index` as the names for the usize vs signed-BigInt pair? --> 🤖 Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Adds
list.get?(index)(safe indexed lookup returning an option) andunwrap_or.🤖