Question

Can somebody please provide some sample code to strip diacritical marks (i.e., replace characters having accents, umlauts, etc., with their unaccented, unumlauted, etc., character equivalents, e.g., every accented é would become a plain ASCII e) from a UnicodeString using the ICU library in C++? E.g.:

UnicodeString strip_diacritics( UnicodeString const &s ) {
    UnicodeString result;
    // ...
    return result;
}

Assume that s has already been normalized. Thanks.

Answer 1

After more searching elsewhere:

UErrorCode status = U_ZERO_ERROR;
UnicodeString result;

// 's16' is the UTF-16 string to have diacritics removed
Normalizer::normalize( s16, UNORM_NFKD, 0, result, status );
if ( U_FAILURE( status ) )
  // complain

// code to convert UTF-16 's16' to UTF-8 std::string 's8' elided

string buf8;
buf8.reserve( s8.length() );
for ( string::const_iterator i = s8.begin(); i != s8.end(); ++i ) {
  char const c = *i;
  if ( isascii( c ) )
    buf8.push_back( c );
}
// result is in buf8

which is O(n).