# 1.0.0-beta.12 Concrete Vector Query And Prefix Parity

Status: release scope for `1.0.0-beta.12`.

`1.0.0-beta.12` is a source-authored standard-library/helper parity release for
current concrete vectors. It keeps the `1.0.0-beta` source language, typed core,
runtime, ABI/layout, and compiler-known `std.vec.*` runtime names unchanged.

## Scope

- Add `count_of`, `starts_with`, `without_prefix`, `ends_with`, and
  `without_suffix` to `std.vec_i64`.
- Add `count_of` to `std.vec_f64`.
- Keep helpers ordinary Slovo source over the existing concrete vector runtime
  names, equality, `len`, `at`, and already staged recursive helpers.
- Extend explicit source-helper project coverage for repeated `count_of`
  results and prefix/suffix empty, mismatch, exact, and longer-than-input
  cases where applicable.
- Bump the Glagol package version to `1.0.0-beta.12`.
- Update README, language docs, compiler docs, and the post-beta roadmap.

## Public Contract

The helper additions are concrete-family helpers:

- `std.vec_i64.count_of(values,target)` counts `i64` elements equal to
  `target`.
- `std.vec_i64.starts_with(values,prefix)` and
  `std.vec_i64.ends_with(values,suffix)` treat empty prefixes/suffixes and
  exact full-vector matches as true, reject mismatches, and reject longer
  prefix/suffix inputs.
- `std.vec_i64.without_prefix(values,prefix)` and
  `std.vec_i64.without_suffix(values,suffix)` return the unmatched original
  vector or the remaining vector after a match.
- `std.vec_f64.count_of(values,target)` counts `f64` elements equal to
  `target`.

## Explicit Non-Scope

- no source-language syntax change
- no typed-core or lowering change
- no runtime implementation change
- no new compiler-known stdlib or runtime names
- no executable generics or generic stdlib dispatch
- no maps or sets
- no iterators
- no mutable vector operations
- no slice/view APIs
- no ABI/layout stability promise
- no performance claim
- no stable stdlib/API freeze

## Checks

Focused checks for this slice:

- `cargo test --manifest-path compiler/Cargo.toml --test standard_vec_i64_source_helpers_alpha --test standard_vec_f64_source_helpers_alpha`
- `cargo fmt --manifest-path compiler/Cargo.toml --check`
- `git diff --check -- compiler/tests/standard_vec_i64_source_helpers_alpha.rs compiler/tests/standard_vec_f64_source_helpers_alpha.rs compiler/Cargo.toml compiler/Cargo.lock README.md docs/POST_BETA_ROADMAP.md docs/language/ROADMAP.md docs/language/RELEASE_NOTES.md docs/language/SPEC-v1.md docs/compiler/ROADMAP.md docs/compiler/RELEASE_NOTES.md .llm/BETA_12_CONCRETE_VECTOR_QUERY_AND_PREFIX_PARITY.md`