Function regdump

src/engine/regexp.cpp:1173–1210

- regdump - dump a regexp onto stdout in vaguely comprehensible form */

 - regdump - dump a regexp onto stdout in vaguely comprehensible form
 */
void
regdump( regexp *r )
{
    char *s;
    char op = EXACTLY; /* Arbitrary non-END op. */
    char *next;


    s = r->program + 1;
    while (op != END) { /* While that wasn't END last time... */
        op = OP(s);
        out_printf("%2d%s", s-r->program, regprop(s));  /* Where, what. */
        next = regnext(s);
        if (next == NULL)       /* Next ptr. */
            out_printf("(0)");
        else
            out_printf("(%d)", (s-r->program)+(next-s));
        s += 3;
        if (op == ANYOF || op == ANYBUT || op == EXACTLY) {
            /* Literal string, where present. */
            while (*s != '\0') {
                out_putc(*s);
                s++;
            }
            s++;
        }
        out_putc('\n');
    }

    /* Header fields of interest. */
    if (r->regstart != '\0')
        out_printf("start `%c' ", r->regstart);
    if (r->reganch)
        out_printf("anchored ");
    if (r->regmust != NULL)
        out_printf("must have \"%s\"", r->regmust);
    out_printf("\n");
}

/*
 - regprop - printable representation of opcode