Struct rpat 

pub struct rpat {
    pub wbranch_visits: HashMap<usize, Vec<u8>>,
    pub patbeginp: [usize; 9],
    pub patendp: [usize; 9],
    pub captures_set: u32,
    pub errsfound: i32,
}

State accumulated during a single patmatch walk. C uses per-thread globals (patbeginp[] / patendp[] for captures); the Rust port encapsulates them in this struct passed by &mut. Rule D: this struct represents matcher-internal scratch state (analogous to struct rpat pattrystate at pattern.c:248), not a bag-of-globals from unrelated subsystems.

C counterpart: struct rpat at pattern.c:248.

Fields

wbranch_visits: HashMap<usize, Vec<u8>>

Per-P_WBRANCH visit bitmap, keyed by WBRANCH-opcode offset. Mirrors C’s Upat ptrp (pattern.c:3217): every WBRANCH carries an 8-byte payload sized as union upat — initialised to NULL, then lazily filled by patmatch with a buffer the size of the input string. Each byte tracks “have we already tried this WBRANCH at this input position with at most this many errors?”. On revisit at the same position with the same-or-fewer errors, C returns 0 to bound the recursion (pattern.c:3245-3248). The Rust port keeps the bitmap on rpat (per-pattry call) instead of inside the bytecode payload so the bytecode stays read-only — the key is the WBRANCH offset; the value is a Vec the size of the input. Without it, (fo#)# against ANY input that requires the closure to consume at least one char per iteration (like “ffo”) burns through PATMATCH_MAX_DEPTH and aborts.

patbeginp: [usize; 9]

patendp: [usize; 9]

captures_set: u32

parsfound from Src/pattern.c (per c:2957/c:2989 references). Two-stripe bitmap: bits 0..NSUBEXP track per-group P_OPEN first-write (patbeginp[i] committed); bits NSUBEXP..2*NSUBEXP track per-group P_CLOSE first-write (patendp[i] committed). Bit n-1 (open) = 1 << (n-1); bit n-1+NSUBEXP (close) = 1 << (n-1+NSUBEXP). Width u32 to fit 2*NSUBEXP = 18 bits. The prior u16 width with a single-stripe (close-only) bit allowed P_OPEN to re-overwrite patbeginp[i] on every backtrack iteration — turning the SECOND capture’s start offset into the FIRST iteration’s, e.g. (*)-(*) against hello-world returned match[2] = "hello-world" instead of the right "world".

errsfound: i32

Port of file-static int errsfound from Src/pattern.c:2046. Cumulative edit-count for approximate-match (#aN). Reset to 0 at the top of each pattry, incremented on P_EXACTLY mismatches when glob_flags & 0xff > 0 (the substitution-budget byte).

Implementations

impl rpat

pub fn new() -> Self

Trait Implementations

impl Clone for rpat

fn clone(&self) -> rpat

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.