1void
2constant(sv)
3    PREINIT:
4#ifdef dXSTARG
5	dXSTARG; /* Faster if we have it.  */
6#else
7	dTARGET;
8#endif
9	STRLEN		len;
10        int		type;
11	IV		iv;
12	/* NV		nv;	Uncomment this if you need to return NVs */
13	const char	*pv;
14    INPUT:
15	SV *		sv;
16        const char *	s = SvPV(sv, len);
17    PPCODE:
18        /* Change this to constant(aTHX_ s, len, &iv, &nv);
19           if you need to return both NVs and IVs */
20	type = constant(aTHX_ s, len, &iv, &pv);
21      /* Return 1 or 2 items. First is error message, or undef if no error.
22           Second, if present, is found value */
23        switch (type) {
24        case PERL_constant_NOTFOUND:
25          sv =
26	    sv_2mortal(newSVpvf("%s is not a valid LMDB_File macro", s));
27          PUSHs(sv);
28          break;
29        case PERL_constant_NOTDEF:
30          sv = sv_2mortal(newSVpvf(
31	    "Your vendor has not defined LMDB_File macro %s, used",
32				   s));
33          PUSHs(sv);
34          break;
35        case PERL_constant_ISIV:
36          EXTEND(SP, 1);
37          PUSHs(&PL_sv_undef);
38          PUSHi(iv);
39          break;
40	/* Uncomment this if you need to return NOs
41        case PERL_constant_ISNO:
42          EXTEND(SP, 1);
43          PUSHs(&PL_sv_undef);
44          PUSHs(&PL_sv_no);
45          break; */
46	/* Uncomment this if you need to return NVs
47        case PERL_constant_ISNV:
48          EXTEND(SP, 1);
49          PUSHs(&PL_sv_undef);
50          PUSHn(nv);
51          break; */
52        case PERL_constant_ISPV:
53          EXTEND(SP, 1);
54          PUSHs(&PL_sv_undef);
55          PUSHp(pv, strlen(pv));
56          break;
57	/* Uncomment this if you need to return PVNs
58        case PERL_constant_ISPVN:
59          EXTEND(SP, 1);
60          PUSHs(&PL_sv_undef);
61          PUSHp(pv, iv);
62          break; */
63	/* Uncomment this if you need to return SVs
64        case PERL_constant_ISSV:
65          EXTEND(SP, 1);
66          PUSHs(&PL_sv_undef);
67          PUSHs(sv);
68          break; */
69	/* Uncomment this if you need to return UNDEFs
70        case PERL_constant_ISUNDEF:
71          break; */
72	/* Uncomment this if you need to return UVs
73        case PERL_constant_ISUV:
74          EXTEND(SP, 1);
75          PUSHs(&PL_sv_undef);
76          PUSHu((UV)iv);
77          break; */
78	/* Uncomment this if you need to return YESs
79        case PERL_constant_ISYES:
80          EXTEND(SP, 1);
81          PUSHs(&PL_sv_undef);
82          PUSHs(&PL_sv_yes);
83          break; */
84        default:
85          sv = sv_2mortal(newSVpvf(
86	    "Unexpected return type %d while processing LMDB_File macro %s, used",
87               type, s));
88          PUSHs(sv);
89        }
90