//	"123 abc 456".findAll('[0-9]*', 1) // returns ['123']
//	"123 abc 456".findAll('xyz') // returns []
func Regex() cel.EnvOption {
	return cel.Lib(regexLib)
}

var regexLib = &regex{}

type regex struct{}

func (*regex) LibraryName() string {
	return "k8s.regex"
}

var regexLibraryDecls = map[string][]cel.FunctionOpt{
	"find": {

kind: DestinationRule
metadata:
  name: regex
  namespace: testns
spec:
  host: regex.extsvc.com
  subsets:
    - name: v1
      labels:
        version: v1
    - name: v2
      labels:
        version: v2
---
apiVersion: networking.istio.io/v1alpha3
kind: VirtualService
metadata:
  name: regex-route
  namespace: testns
spec:
  hosts:
    - regex.extsvc.com
  http:
    - match:

        } else {
            paths.split(PATHS_SEPARATOR).joinToString("|") {
                wildcardsToRegexPatternString(normalizeFilePattern(it))
            }.toRegex(if (!isCaseSensitive) EnumSet.of(RegexOption.IGNORE_CASE) else emptySet())
        }

    private
    companion object {
        const val PATHS_SEPARATOR = ";"
    }

      filtered_ops.push_back(func);
    }
    return;
  }

  llvm::Regex op_regex(tac_filter.op_filter().op_name_pattern());
  module.walk([&](Operation* op) {
    auto named_loc = mlir::dyn_cast<NameLoc>(op->getLoc());
    if (!named_loc) {
      return;
    }
    if (!op_regex.match(named_loc.getName())) {
      return;
    }

/**
 */
@Named
@Singleton
public class DefaultSettingsValidator implements SettingsValidator {

    private static final String ID = "[\\w.-]+";
    private static final Pattern ID_REGEX = Pattern.compile(ID);

    private final SettingsBuilder settingsBuilder;

    @Inject
    public DefaultSettingsValidator(SettingsBuilder settingsBuilder) {
        this.settingsBuilder = settingsBuilder;
    }

                    .replace("\"sha1\":\\s+\"\\w+\"".toRegex(), "\"sha1\": \"\"")
                    .replace("\"sha256\":\\s+\"\\w+\"".toRegex(), "\"sha256\": \"\"")
                    .replace("\"md5\":\\s+\"\\w+\"".toRegex(), "\"md5\": \"\"")
                it.writeText(content)
            }
        }
    }

    // For local consumption by tests

                .replace("\"sha1\":\\s+\"\\w+\"".toRegex(), "\"sha1\": \"\"")
                .replace("\"sha256\":\\s+\"\\w+\"".toRegex(), "\"sha256\": \"\"")
                .replace("\"md5\":\\s+\"\\w+\"".toRegex(), "\"md5\": \"\"")
            it.writeText(content)
        }
    }
}

                    safeRegexMatch:
                      regex: (?i)example\.com
                - header:
                    name: :authority
                    safeRegexMatch:
                      regex: (?i)prefix\.example\..*
                - header:
                    name: :authority
                    safeRegexMatch:
                      regex: (?i).*\.example\.com
                - header:

        }
    }

    public void addClient(final String regex, final CrawlerClient client) {
        if (StringUtil.isBlank(regex)) {
            throw new CrawlerSystemException("A regular expression is null.");
        }
        if (client == null) {
            throw new CrawlerSystemException("CrawlerClient is null.");
        }
        clientMap.put(Pattern.compile(regex), client);
    }

                      safeRegex:
                        regex: .*/ns/istio-system/.*
            - orIds:
                ids:
                - authenticated:
                    principalName:
                      safeRegex:
                        regex: .+
                - authenticated:
                    principalName:
                      safeRegex:
                        regex: spiffe://.*/ns/foo/sa/all-td