ROUP

ROUP is a strict, safe Rust parser for OpenMP and OpenACC directives in C, C++, and Fortran source forms. It returns typed syntax trees suitable for compiler frontends and source tools.

The parser has four deliberate rules:

• A successful result contains typed directive, clause, selector, locator, and host-expression data.
• A problem is returned immediately as one structured diagnostic. Trailing input, unknown fields, incompatible clauses, and unavailable features are not ignored.
• Version selection is cumulative. An exact specification mode rejects syntax introduced later, while continuing to accept standardized syntax from older specifications even if a later specification deprecated or removed it.
• Standard spelling aliases are accepted at the grammar boundary and map to a canonical semantic representation.

The root roup package is the complete parser and contains no unsafe Rust. A separate optional roup-capi package provides an opaque-handle C ABI. The ompparser and accparser compatibility libraries are consumers of that ABI, not alternate parser implementations.