This is a Stage-1 mirror of pyparsing/pyparsing (MIT).

Upstream: https://github.com/pyparsing/pyparsing
Original author: Paul McGuire
Upstream license: MIT (see upstream LICENSE, preserved in this tree).

What changed vs upstream (behavior-identical port):
- `pyparsing/core.py`: `CharsNotIn.parseImpl` and `White.parseImpl`
  execute their remainder scan loops in the compiled
  `pyparsing-rust-core` crate (exposed as `pyparsing._pyparsing`).
  First-character checks, length checks, and every `ParseException`
  site stay in Python; the Rust kernels only advance a code-point
  index over the same membership predicate (verified code-point for
  code-point, including lone surrogates). Every other module —
  `ParserElement` dispatch, `preParse`, `Word` (regex fast path),
  `ParseResults`, helpers, common, testing, unicode, diagram — is the
  upstream source verbatim.
- Build backend: flit_core → maturin (PyO3 extension module
  `pyparsing._pyparsing`).
