/// <summary>
/// For all letters in the bdd add their lower and upper case equivalents.
/// This operation depends on culture for i, I, '\u0130', and '\u0131';
/// culture="" means InvariantCulture while culture=null means to use the current culture.
/// </summary>
public BDD Apply(BDD bdd, string?culture = null)
{
// First get the culture specific relation
IgnoreCaseRelation relation = GetIgnoreCaseRelation(culture);
if (_solver.And(relation.InstanceDomain, bdd).IsEmpty)
{
// No elements need to be added
return(bdd);
}
// Compute the set of all characters that are equivalent to some element in bdd.
// restr is the relation restricted to the relevant characters in bdd.
// This conjunction works because bdd is unspecified for bits > 15.
BDD restr = _solver.And(bdd, relation.Instance);
// ShiftRight essentially produces the LHS of the relation (char X char) that restr represents.
BDD ignorecase = _solver.ShiftRight(restr, 16);
// The final set is the union of all the characters.
return(_solver.Or(ignorecase, bdd));
}
private static void WriteIgnoreCaseBDD(StreamWriter sw)
{
sw.WriteLine(" /// <summary>Serialized BDD for mapping characters to their case-ignoring equivalence classes in the default (en-US) culture.</summary>");
var solver = new CharSetSolver();
Dictionary <char, BDD> ignoreCase = ComputeIgnoreCaseDictionary(solver, new CultureInfo(DefaultCultureName));
BDD ignorecase = solver.False;
foreach (KeyValuePair <char, BDD> kv in ignoreCase)
{
BDD a = solver.CreateCharSetFromRange(kv.Key, kv.Key);
BDD b = kv.Value;
ignorecase = solver.Or(ignorecase, solver.And(solver.ShiftLeft(a, 16), b));
}
sw.Write(" public static readonly long[] IgnoreCaseEnUsSerializedBDD = ");
GeneratorHelper.WriteInt64ArrayInitSyntax(sw, ignorecase.Serialize());
sw.WriteLine(";");
}
private static void WriteIgnoreCaseBDD(StreamWriter sw)
{
sw.WriteLine(" /// <summary>Serialized BDD for mapping characters to their case-ignoring equivalence classes in the default (en-US) culture.</summary>");
var solver = new CharSetSolver();
List <EquivalenceClass> ignoreCaseEquivalenceClasses = ComputeIgnoreCaseEquivalenceClasses(solver, new CultureInfo(DefaultCultureName));
BDD ignorecase = solver.False;
foreach (EquivalenceClass ec in ignoreCaseEquivalenceClasses)
{
// Create the Cartesian product of ec._set with itself
BDD crossproduct = solver.And(solver.ShiftLeft(ec._set, 16), ec._set);
// Add the product into the overall lookup table
ignorecase = solver.Or(ignorecase, crossproduct);
}
sw.Write(" public static readonly byte[] IgnoreCaseEnUsSerializedBDD = ");
GeneratorHelper.WriteByteArrayInitSyntax(sw, ignorecase.SerializeToBytes());
sw.WriteLine(";");
}
