wcsstr method

int wcsstr(List<wchar_t> haystack, List<wchar_t> needle)

Finds the first occurrence of the wide substring needle in the wide string haystack.

Returns the index of the substring, or -1 if the substring is not found.

Implementation

int wcsstr(List<wchar_t> haystack, List<wchar_t> needle) {
  if (needle.isEmpty) return 0;
  for (int i = 0; i <= haystack.length - needle.length; i++) {
    bool match = true;
    for (int j = 0; j < needle.length; j++) {
      if (haystack[i + j] != needle[j]) {
        match = false;
        break;
      }
    }
    if (match) return i;
  }
  return -1;
}