String StringUtil::Implode(const Variant& items, const String& delim) {
if (!isContainer(items)) {
throw_param_is_not_container();
}
int size = getContainerSize(items);
if (size == 0) return "";
String* sitems = (String*)smart_malloc(size * sizeof(String));
int len = 0;
int lenDelim = delim.size();
int i = 0;
for (ArrayIter iter(items); iter; ++iter) {
new (&sitems[i]) String(iter.second().toString());
len += sitems[i].size() + lenDelim;
i++;
}
len -= lenDelim; // always one delimiter less than count of items
assert(i == size);
String s = String(len, ReserveString);
char *buffer = s.bufferSlice().ptr;
const char *sdelim = delim.data();
char *p = buffer;
for (int i = 0; i < size; i++) {
String &item = sitems[i];
if (i && lenDelim) {
memcpy(p, sdelim, lenDelim);
p += lenDelim;
}
int lenItem = item.size();
if (lenItem) {
memcpy(p, item.data(), lenItem);
p += lenItem;
}
sitems[i].~String();
}
smart_free(sitems);
assert(p - buffer == len);
s.setSize(len);
return s;
}
String StringUtil::Implode(const Variant& items, const String& delim,
const bool checkIsContainer /* = true */) {
if (checkIsContainer && !isContainer(items)) {
throw_param_is_not_container();
}
int size = getContainerSize(items);
if (size == 0) return empty_string();
req::vector<String> sitems;
sitems.reserve(size);
size_t len = 0;
size_t lenDelim = delim.size();
for (ArrayIter iter(items); iter; ++iter) {
sitems.emplace_back(iter.second().toString());
len += sitems.back().size() + lenDelim;
}
len -= lenDelim; // always one delimiter less than count of items
assert(sitems.size() == size);
String s = String(len, ReserveString);
char *buffer = s.mutableData();
const char *sdelim = delim.data();
char *p = buffer;
String &init_str = sitems[0];
int init_len = init_str.size();
memcpy(p, init_str.data(), init_len);
p += init_len;
for (int i = 1; i < size; i++) {
String &item = sitems[i];
memcpy(p, sdelim, lenDelim);
p += lenDelim;
int lenItem = item.size();
memcpy(p, item.data(), lenItem);
p += lenItem;
}
assert(p - buffer == len);
s.setSize(len);
return s;
}
