GR
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Grain Preview.
At a glance
| Purpose | Grain source code: a statically typed functional language that compiles to WebAssembly. |
| Extensions | .gr |
| Poka parser | poka-grain |
| Viewer | poka-metadata-card-viewer |
| Depth tier | Metadata card (see Depth tiers) |
| Breadth tier | B4 Summary (see Breadth tiers) |
How much Poka reads
B4 Summary. The container and metadata are read and summarised (counts, properties, structure), but the main content is not rendered.
Confidence: medium (the reviewer read the code). Basis: Reviewed 2026-10-26: read parsers/poka-grain/src/main.rs (325 lines) and plugin.json in full. The crate has no unit tests and no tests/samples.rs, and the corpus has no .gr sample, so the tier rests on reading the code. Covers .gr. The output is a metadata card of counts found by matching text line by line: module, include and from-include, let and let mut bindings, provide, records, enums and abstract types, anonymous functions, foreign imports, exceptions, test cases and line counts. Judgement: B4, because the structure is summarised but the source itself is never shown.
What Poka does not read
- The source text is not shown: the card carries only counts and a few sample names, with no code view or highlighting
- Constructs are found by matching text line by line, not by parsing, so multi-line declarations, nested or indented definitions and keywords inside strings or comments can be miscounted
- Counts of named items stop where their name list is capped (provides at 64, let bindings at 64, records at 32, enums at 32, abstract types at 32), so a larger file under-reports them
- Files over 32 MiB are cut to the first 32 MiB (the card says so)
- Text that is not UTF-8 is decoded with replacement characters; no other encoding is tried
Libraries
Libraries Poka uses or has assessed for this format, with the status, licence and language the registry records.
- Grain compiler (grain-lang/grain) (candidate; LGPL-3.0; Reason/OCaml; https://github.com/grain-lang/grain) — Parser is internal to the compiler, not a standalone library. Repo language breakdown is mostly Reason with some OCaml. No tree-sitter grammar found (tree-sitter-grain URL returned 404).
Sources
- parsers/poka-grain/src/main.rs
- parsers/poka-grain/plugin.json