Creating a Custom Character Map: Example

The following code sample creates a character map similar to the standard character map except that the characters ’&’ and ’#’ are not mapped, the dash character ’-’ is deleted and the default case folding for the letter ’I’ is changed to that for Turkish. We start by checking to see if our character map is already created.

static char map_name = "our-turkic-map" ;
static char from_set = "&#-I" ;
/* ampersand, pound,  delete it,       lower i no dot */
static int  to_set = { 0x0026,  0x0023, LKT_CHAR_DELETE, 0x0131 } ;
lpar_t      mapname ;     /* name of our character map */
lpar_t      mapdef ;      /* definition parameters for creating map */
lpar_t      mapping ;     /* one mapping clause in mapdef */
dvkerr_t    err ;         /* return status of devkit function calls */
/* create descriptor for our character map */
mapname = lpar_create_str(LPAR_STR_CHARMAP, map_name) ;
/* create only if doesn't already exist */
err = lkt_charmap_list(mapdesc, NULL) ;
if (DVKERR(err) == DVK_ERR_DBNOTFOUND) {
    /* create parameter list */
    mapdef = lkt_list_create();
    /* fold case */
    lkt_list_append(mapdef, lpar_create_int(LPAR_INT_FOLDCLASS, LKT_CCLASS_CASE));
    /* fold diacritics and normalize */
    lkt_list_append(mapdef,
                    lpar_create_int(LPAR_INT_FOLDCLASS, LKT_CCLASS_DIACRITICS));
    /* map all whitespace to blank */
    mapping = lpar_create_list(LPAR_LST_MAP);
    lkt_list_append(mapping, lpar_create_int(LPAR_INT_FROM_CLASS,
                                             LKT_CCLASS_WHITESPACE));   
    lkt_list_append(mapping, lpar_create_blk(LPAR_BLK_TO_CHARS, " ", 1));
    lkt_list_append(mapdef, mapping);
    /* map all punctuation to blank */
    mapping = lpar_create_list(LPAR_LST_MAP);
    lkt_list_append(mapping, lpar_create_int(LPAR_INT_FROM_CLASS, 
                                             LKT_CCLASS_PUNCTUATION));
    lkt_list_append(mapping, lpar_create_blk(LPAR_BLK_TO_CHARS, " ", 1));
    lkt_list_append(mapdef, mapping);
    /* now apply our special mappings */
    mapping = lpar_create_list(LPAR_LST_MAP);
    lkt_list_append(mapping, lpar_create_blk(LPAR_BLK_FROM_CHARS, from_set, 4));
    lkt_list_append(mapping, lpar_create_intarr(LPAR_INTARR_TO_UCODES, to_set, 4));
    lkt_list_append(mapdef, mapping);
    /* create the character map */
    err = lkt_create_charmap(mapname, mapdef);
    if (DVKERR(err)) {
            /* handle error here */
    }
}