static struct value *lns_value_of_type(struct info *info, struct regexp *rx) {
struct value *result = make_value(V_REGEXP, ref(info));
if (rx)
result->regexp = ref(rx);
else
result->regexp = regexp_make_empty(ref(info));
return result;
}
/*
* Lens primitives
*/
struct value *lns_make_prim(enum lens_tag tag, struct info *info,
struct regexp *regexp, struct string *string) {
struct lens *lens = NULL;
struct value *exn = NULL;
struct fa *fa_slash = NULL;
struct fa *fa_key = NULL;
struct fa *fa_isect = NULL;
/* Typecheck */
if (tag == L_KEY) {
exn = str_to_fa(info, "(.|\n)*/(.|\n)*", &fa_slash);
if (exn != NULL)
goto error;
exn = regexp_to_fa(regexp, &fa_key);
if (exn != NULL)
goto error;
fa_isect = fa_intersect(fa_slash, fa_key);
if (! fa_is_basic(fa_isect, FA_EMPTY)) {
exn = make_exn_value(info,
"The key regexp /%s/ matches a '/'",
regexp->pattern->str);
goto error;
}
fa_free(fa_isect);
fa_free(fa_key);
fa_free(fa_slash);
fa_isect = fa_key = fa_slash = NULL;
} else if (tag == L_LABEL) {
if (strchr(string->str, SEP) != NULL) {
exn = make_exn_value(info,
"The label string \"%s\" contains a '/'",
string->str);
goto error;
}
} else if (tag == L_DEL) {
int cnt;
const char *dflt = string->str;
cnt = regexp_match(regexp, dflt, strlen(dflt), 0, NULL);
if (cnt != strlen(dflt)) {
char *s = escape(dflt, -1);
char *r = escape(regexp->pattern->str, -1);
exn = make_exn_value(info,
"del: the default value '%s' does not match /%s/",
s, r);
FREE(s);
FREE(r);
goto error;
}
}
/* Build the actual lens */
lens = make_lens(tag, info);
lens->regexp = regexp;
lens->string = string;
lens->key = (tag == L_KEY || tag == L_LABEL || tag == L_SEQ);
lens->value = (tag == L_STORE);
lens->consumes_value = (tag == L_STORE);
lens->atype = regexp_make_empty(info);
if (tag == L_DEL || tag == L_STORE || tag == L_KEY) {
lens->ctype = ref(regexp);
} else if (tag == L_LABEL || tag == L_SEQ || tag == L_COUNTER) {
lens->ctype = regexp_make_empty(info);
} else {
assert(0);
}
return make_lens_value(lens);
error:
fa_free(fa_isect);
fa_free(fa_key);
fa_free(fa_slash);
return exn;
}
