I branched from the C to Fortran transpiler to create partial transpilers from C++ and C to Fortran using Codex and Claude.
The mapping of C++ language constructs, including std::mdspan, to modern Fortran is described in the readme and here.
source & further reading
fortran-lang.discourse.group — original article
FOSSIL v3.0.0 is out
Fparse: Fortran function parser
LFortran + Coding Agents