private RxNode <TLetter> ComputeRx()
{
var regex = default(RxNode <TLetter>);
using (var enumerator = this.tokens.Values.GetEnumerator()) {
if (!enumerator.MoveNext())
{
throw new InvalidOperationException("No terminals have been defined");
}
regex = enumerator.Current;
while (enumerator.MoveNext())
{
regex = new RxAlternation <TLetter>(enumerator.Current, regex);
}
}
return(regex);
}
public RxNode <LetterId> Alternation(RxAlternation <TLetter> node, Func <RxMatch <TLetter>, ICollection <LetterId> > context)
{
return(new RxAlternation <LetterId>(node.Left.Visit(this, context), node.Right.Visit(this, context)));
}
NfaState <TLetter> IRegexVisitor <TLetter, NfaState <TLetter>, NfaState <TLetter> > .Alternation(RxAlternation <TLetter> node, NfaState <TLetter> context)
{
var left = this.Create();
context.AddEpsilonTransition(left);
var right = this.Create();
context.AddEpsilonTransition(right);
var target = this.Create();
node.Left.Visit(this, left).AddEpsilonTransition(target);
node.Right.Visit(this, right).AddEpsilonTransition(target);
return(target);
}
public object Alternation(RxAlternation <TLetter> node, Func <RangeSet <TLetter>, object, RangeSet <TLetter> > context)
{
node.Left.Visit(this, context);
node.Right.Visit(this, context);
return(null);
}
RxNode <TLetter> IRegexVisitor <TLetter, SymbolId, RxNode <TLetter> > .Alternation(RxAlternation <TLetter> node, SymbolId context)
{
return(node.Left.Visit(this, context) ?? node.Right.Visit(this, context));
}
