public Regex Parse(string regularExpression)
{
var grammar = new RegexGrammar();
var parseEngine = new ParseEngine(grammar, new ParseEngineOptions(optimizeRightRecursion: true));
var parseRunner = new ParseRunner(parseEngine, regularExpression);
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
{
throw new Exception(
$"Unable to parse regular expression. Error at position {parseRunner.Position}.");
}
}
if (!parseEngine.IsAccepted())
{
throw new Exception(
$"Error parsing regular expression. Error at position {parseRunner.Position}");
}
var parseForest = parseEngine.GetParseForestRootNode();
var parseTree = new InternalTreeNode(
parseForest as IInternalForestNode,
new SelectFirstChildDisambiguationAlgorithm());
var regexVisitor = new RegexVisitor();
parseTree.Accept(regexVisitor);
return(regexVisitor.Regex);
}
public Regex Parse(string regularExpression)
{
var grammar = new RegexGrammar();
var parseEngine = new ParseEngine(grammar, new ParseEngineOptions(optimizeRightRecursion: true));
var parseRunner = new ParseRunner(parseEngine, regularExpression);
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
throw new Exception(
$"Unable to parse regular expression. Error at position {parseRunner.Position}.");
}
if (!parseEngine.IsAccepted())
throw new Exception(
$"Error parsing regular expression. Error at position {parseRunner.Position}");
var parseForest = parseEngine.GetParseForestRootNode();
var parseTree = new InternalTreeNode(
parseForest as IInternalForestNode,
new SelectFirstChildDisambiguationAlgorithm());
var regexVisitor = new RegexVisitor();
parseTree.Accept(regexVisitor);
return regexVisitor.Regex;
}
public Regex Parse(string regularExpression)
{
var grammar = new RegexGrammar();
var parseEngine = new ParseEngine(grammar, new ParseEngineOptions());
var parseRunner = new ParseRunner(parseEngine, regularExpression);
while (!parseRunner.EndOfStream())
{
if (!parseRunner.Read())
{
throw new Exception(
$"Unable to parse regular expression. Error at position {parseRunner.Position}.");
}
}
if (!parseEngine.IsAccepted())
{
throw new Exception(
$"Error parsing regular expression. Error at position {parseRunner.Position}");
}
var parseTree = parseEngine.GetParseTree();
var regexVisitor = new RegexVisitor();
parseTree.Accept(regexVisitor);
return(regexVisitor.Regex);
}
private static EbnfLexerRuleFactor VisitLexerRuleFactorNode(IInternalTreeNode node)
{
for (int c = 0; c < node.Children.Count; c++)
{
var child = node.Children[c];
if (child.NodeType != TreeNodeType.Internal)
continue;
var internalNode = child as IInternalTreeNode;
var symbolValue = internalNode.Symbol.Value;
if (EbnfGrammar.Literal == symbolValue)
return new EbnfLexerRuleFactorLiteral(
VisitLiteralNode(internalNode));
if (RegexGrammar.Regex == symbolValue)
{
var regexVisitor = new RegexVisitor();
internalNode.Accept(regexVisitor);
return new EbnfLexerRuleFactorRegex(regexVisitor.Regex);
}
}
throw UnreachableCodeException();
}
private EbnfFactor VisitFactorNode(IInternalTreeNode node)
{
for (int c = 0; c < node.Children.Count; c++)
{
var child = node.Children[c];
switch (child.NodeType)
{
case TreeNodeType.Internal:
var internalNode = child as IInternalTreeNode;
var symbolValue = internalNode.Symbol.Value;
if (EbnfGrammar.QualifiedIdentifier == symbolValue)
return new EbnfFactorIdentifier(
VisitQualifiedIdentifierNode(internalNode));
if (EbnfGrammar.Literal == symbolValue)
return new EbnfFactorLiteral(
VisitLiteralNode(internalNode));
if (EbnfGrammar.Repetition == symbolValue)
return VisitRepetitionNode(internalNode);
if (EbnfGrammar.Optional == symbolValue)
return VisitOptionalNode(internalNode);
if (EbnfGrammar.Grouping == symbolValue)
return VisitGroupingNode(internalNode);
if (RegexGrammar.Regex == symbolValue)
{
var regexVisitor = new RegexVisitor();
internalNode.Accept(regexVisitor);
return new EbnfFactorRegex(regexVisitor.Regex);
}
break;
case TreeNodeType.Token:
break;
}
}
throw UnreachableCodeException();
}
