Function parse_rel

src/cypher/cypher.c:730–765

Parse relationship: -[:TYPE|TYPE2*min..max]-> or <-[...]- */

/* Parse relationship: -[:TYPE|TYPE2*min..max]-> or <-[...]-  */
static int parse_rel(parser_t *p, cbm_rel_pattern_t *out) {
    memset(out, 0, sizeof(*out));
    out->min_hops = SKIP_ONE;
    out->max_hops = SKIP_ONE;

    /* Check for leading < (inbound) */
    bool leading_lt = match(p, TOK_LT);
    if (!expect(p, TOK_DASH)) {
        return CBM_NOT_FOUND;
    }

    /* Optional bracket content */
    if (match(p, TOK_LBRACKET)) {
        if (parse_rel_bracket(p, out) < 0) {
            return CBM_NOT_FOUND;
        }
    }

    if (!expect(p, TOK_DASH)) {
        return CBM_NOT_FOUND;
    }

    /* Check for trailing > (outbound) */
    bool trailing_gt = match(p, TOK_GT);

    /* Determine direction */
    if (leading_lt && !trailing_gt) {
        out->direction = heap_strdup("inbound");
    } else if (!leading_lt && trailing_gt) {
        out->direction = heap_strdup("outbound");
    } else {
        out->direction = heap_strdup("any");
    }

    return 0;
}

/* ── Expression tree helpers ────────────────────────────────────── */