private Regex BuildCore(PatternNode pattern, bool exactMatch)
{
Visit(pattern);
if (exactMatch)
{
builder.AppendDollar();
}
return(RegexFactory.Create(builder.ToString()));
}
public bool TryCompile(
string pattern,
[NotNullWhen(true)] out CompiledPattern?compiledPattern,
[NotNullWhen(false)] out IReadOnlyList <PatternCompilerError>?errors)
{
CheckValue(pattern, nameof(pattern));
var errorsSink = new PatternCompilerErrorsSink();
// 1- Resolve the type of the pattern
var resolvedPattern = resolver.Resolve(pattern);
var type = resolvedPattern.Type;
pattern = resolvedPattern.Pattern;
Regex regex;
ISet <string> variables;
if (type == PatternType.Regex)
{
// 2- Build regex
regex = RegexFactory.Create(pattern);
// 3- Get variable names
var names = regex.GetGroupNames().Where(n => !short.TryParse(n, NumberStyles.None, null, out var _));
variables = new HashSet <string>(names, StringComparer.OrdinalIgnoreCase);
}
else
{
// 2- Parse
if (!parser.TryParse(pattern, errorsSink, out var parsedPattern))
{
compiledPattern = null;
errors = errorsSink.Errors;
return(false);
}
// 3- Validate
if (!validator.Validate(parsedPattern, errorsSink))
{
compiledPattern = null;
errors = errorsSink.Errors;
return(false);
}
// 4- Build regex
regex = PatternRegexBuilder.Build(parsedPattern, type == PatternType.ExactMatch);
// 5- Get variable names
variables = VariableNamesExtractor.Extract(parsedPattern);
}
compiledPattern = new CompiledPattern(
pattern,
type,
regex,
variables);
errors = null;
return(true);
}