private RegexFactor VisitRegexFactorNode(IInternalTreeNode internalNode)
{
RegexAtom atom = null;
RegexIterator?iterator = null;
for (var c = 0; c < internalNode.Children.Count; c++)
{
var child = internalNode.Children[c];
if (child.NodeType != TreeNodeType.Internal)
{
continue;
}
var childInternalNode = child as IInternalTreeNode;
var childInternalNodeSymbolValue = childInternalNode.Symbol.Value;
if (RegexGrammar.Atom == childInternalNodeSymbolValue)
{
atom = VisitRegexAtomNode(childInternalNode);
}
else if (RegexGrammar.Iterator == childInternalNodeSymbolValue)
{
iterator = VisitRegexIteratorNode(childInternalNode);
}
}
if (iterator.HasValue)
{
return(new RegexFactorIterator(
atom,
iterator.Value));
}
return(new RegexFactor(atom));
}
private static Nfa Atom(RegexAtom atom)
{
switch (atom)
{
case RegexAtomAny _:
return(Any());
case RegexAtomCharacter regexAtomCharacter:
return(Character(regexAtomCharacter.Character));
case RegexAtomExpression regexAtomExpression:
return(Expression(regexAtomExpression.Expression));
case RegexAtomSet regexAtomSet:
return(Set(regexAtomSet));
}
throw new InvalidOperationException("Unrecognized regex atom");
}
private static INfa Atom(RegexAtom atom)
{
switch (atom.NodeType)
{
case RegexNodeType.RegexAtomAny:
return(Any());
case RegexNodeType.RegexAtomCharacter:
var regexAtomCharacter = atom as RegexAtomCharacter;
return(Character(regexAtomCharacter.Character));
case RegexNodeType.RegexAtomExpression:
var regexAtomExpression = atom as RegexAtomExpression;
return(Expression(regexAtomExpression.Expression));
case RegexNodeType.RegexAtomSet:
var regexAtomSet = atom as RegexAtomSet;
return(Set(regexAtomSet));
}
throw new InvalidOperationException("Unrecognized regex atom");
}
private static INfa Atom(RegexAtom atom)
{
switch (atom.NodeType)
{
case RegexNodeType.RegexAtomAny:
return Any();
case RegexNodeType.RegexAtomCharacter:
var regexAtomCharacter = atom as RegexAtomCharacter;
return Character(regexAtomCharacter.Character);
case RegexNodeType.RegexAtomExpression:
var regexAtomExpression = atom as RegexAtomExpression;
return Expression(regexAtomExpression.Expression);
case RegexNodeType.RegexAtomSet:
var regexAtomSet = atom as RegexAtomSet;
return Set(regexAtomSet);
}
throw new InvalidOperationException("Unrecognized regex atom");
}
private IRegexFactor VisitRegexFactorNode(IInternalTreeNode node)
{
RegexAtom atom = null;
RegexIterator?iterator = null;
foreach (var internalNode in node.Children.OfType <IInternalTreeNode>())
{
if (internalNode.Is(RegexGrammar.Atom))
{
atom = VisitRegexAtomNode(internalNode);
}
else if (internalNode.Is(RegexGrammar.Iterator))
{
iterator = VisitRegexIteratorNode(internalNode);
}
}
if (iterator.HasValue)
{
return(new RegexFactorIterator(atom, iterator.Value));
}
return(new RegexFactorAtom(atom));
}
public RegexFactor(RegexAtom atom)
{
Atom = atom;
_hashCode = ComputeHashCode();
}
public RegexFactorIterator(RegexAtom atom, RegexIterator iterator)
: base(atom)
{
Iterator = iterator;
_hashCode = ComputeHashCode();
}
public RegexFactorIterator(RegexAtom atom, RegexIterator iterator)
{
Atom = atom;
Iterator = iterator;
}
public RegexFactorAtom(RegexAtom atom)
{
Atom = atom;
}