public static Tuple <BDD, Tuple <BDD, BDD>[]>[] Extract3ByteUTF8Encodings(BDD set)
{
var alg = set.algebra;
CharSetSolver css = alg as CharSetSolver;
if (css == null)
{
throw new AutomataException(AutomataExceptionKind.NotSupported);
}
var surrogates = css.MkCharSetFromRange('\uD800', '\uDFFF');
var threebyterange = css.MkCharSetFromRange('\u0800', '\uFFFF').Diff(surrogates);
var uptoFF = css.MkCharSetFromRange('\0', '\xFF');
var set3 = set & threebyterange;
var lowerpartition = set3.Partition(11);
var b5 = alg.MkBitTrue(5);
var b6 = alg.MkBitTrue(6);
var b7 = alg.MkBitTrue(7);
var b4_false = alg.MkBitFalse(4);
var b6_false = alg.MkBitFalse(6);
var start_mask = b7 & b6 & b5 & b4_false & uptoFF;
var val_mask = b7 & b6_false & uptoFF;
var partition = Array.ConvertAll(lowerpartition, x => new Tuple <BDD, Tuple <BDD, BDD>[]>(
css.OmitBitsAbove(x.Item2 >> 12, 4) & start_mask,
Array.ConvertAll <Tuple <BDD, BDD>, Tuple <BDD, BDD> >(x.Item1.Partition(5),
y => new Tuple <BDD, BDD>(css.OmitBitsAbove(y.Item2 >> 6, 6) & val_mask, y.Item1 & val_mask))
));
return(partition);
}
public static Tuple <BDD, BDD>[] Extract2ByteUTF8Encodings(BDD set)
{
CharSetSolver css = set.algebra as CharSetSolver;
if (css == null)
{
throw new AutomataException(AutomataExceptionKind.NotSupported);
}
var twobyterange = css.MkCharSetFromRange('\x80', '\u07FF');
var uptoFF = css.MkCharSetFromRange('\0', '\xFF');
var b6 = set.algebra.MkBitTrue(6);
var b7 = set.algebra.MkBitTrue(7);
var b5_false = set.algebra.MkBitFalse(5);
var b6_false = set.algebra.MkBitFalse(6);
var byte1_mask = b7 & b6 & b5_false & uptoFF;
var byte2_mask = b7 & b6_false & uptoFF;
var d2 = set & twobyterange;
var partition = d2.Partition(5);
var res = Array.ConvertAll(partition, x => new Tuple <BDD, BDD>(css.OmitBitsAbove(x.Item2 >> 6, 5) & byte1_mask, x.Item1 & byte2_mask));
return(res);
}
