The Vision language reference

The language reference is the second of the four documentation tiers. It is the exhaustive counterpart to the concept guide: where Tier I teaches through running programs, Tier II names the precise rules, accepted types, and current limitations. The nine domains are ordered from the inside of the language outward — values and kinds first, host and network last.

What this tier covers

Each reference domain documents one slice of the language surface: exact grammar, exact accepted types, exact failure tags, exact ownership rules, the compiler-checked fixtures that pin the behavior, and a current-limitations section that discloses compiler gaps rather than papering over them. Every domain cross-references the concept-guide page that introduces it.

The nine domains, in reading order

1. 01 · Values & described thingsExact value types, collections, named shapes, construction, and ownership.
2. 02 · Control flowExact branches, loops, parallel iteration, comparisons, and operators.
3. 03 · Effects & failureFailure clauses, propagation, optional-value proofs, and visible effects.
4. 04 · ConcurrencyTyped channels, joined strands, concurrent failure, and event loops.
5. 05 · Host & C interopby hand raw-C, C library discovery, verb-to-C bindings, and host exposure.
6. 06 · Filesystem & dataFiles, directories, recursive walks, stat, and SQLite-backed databases.
7. 07 · Network & processTCP servers, child programs, environment iteration, and signals.
8. 08 · Generics & monomorphizationClosed type lists, monomorphized verbs, generic kinds, and the diagnostics that guard the boundary.
9. 09 · Construction & absence`built from` and block construction, presence facts at joins and loops, and the absence proofs that bind them.

Beyond the reference

Tier III — the diagnostics reference — keys every compiler diagnostic by its stable code and pairs each one with a verified reproducer and a how-to-fix. Tier IV — the tooling reference — documents the compiler's eleven-verb command-line surface end to end.