import okio.ByteString.Companion.decodeHex
import okio.IOException

/** Example: "0x00,0x08",TLS_RSA_EXPORT_WITH_DES40_CBC_SHA,Y,N,[RFC4346] */
val IANA_CSV_PATTERN = "\"0x(\\w\\w),0x(\\w\\w)\",(\\w+).*".toRegex()

fun parseIanaCsvRow(s: String): SuiteId? {
  if (s.contains("Reserved") || s.contains("Unassigned")) return null
  val matcher = IANA_CSV_PATTERN.matchEntire(s) ?: return null

  companion object {
    private const val TOKEN = "([a-zA-Z0-9-!#$%&'*+.^_`{|}~]+)"
    private const val QUOTED = "\"([^\"]*)\""
    private val TYPE_SUBTYPE = Regex("$TOKEN/$TOKEN")
    private val PARAMETER = Regex(";\\s*(?:$TOKEN=(?:$TOKEN|$QUOTED))?")

    /**
     * Returns a media type for this string.
     *
     * @throws IllegalArgumentException if this is not a well-formed media type.
     */

package okhttp3

import assertk.assertThat
import assertk.assertions.matches
import org.junit.jupiter.api.Test

class OkHttpTest {
  @Test
  fun testVersion() {
    assertThat(OkHttp.VERSION).matches(Regex("[0-9]+\\.[0-9]+\\.[0-9]+(-.+)?"))
  }

 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.util.ArrayList;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Utility class for parsing CSV text
 */
public final class KuromojiCSVUtil {
    private static final char QUOTE = '"';

    private static final char COMMA = ',';

import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.MatchResult;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.jspecify.annotations.NullMarked;
import org.jspecify.annotations.Nullable;

/**

import com.google.common.annotations.J2ktIncompatible;
import com.google.common.base.Preconditions;
import java.io.File;
import java.io.FilenameFilter;
import java.util.regex.Pattern;
import java.util.regex.PatternSyntaxException;

/**
 * File name filter that only accepts files matching a regular expression. This class is thread-safe
 * and immutable.
 *
 * @author Apple Chow
 * @since 1.0
 */

Now you know that whenever you need them you can use them in **FastAPI**.

### Pydantic v1 `regex` instead of `pattern` { #pydantic-v1-regex-instead-of-pattern }

Before Pydantic version 2 and before FastAPI 0.100.0, the parameter was called `regex` instead of `pattern`, but it's now deprecated.

You could still see some code using it:

//// tab | Pydantic v1

     */
    protected void setupListCondition(final PathMappingCB cb, final PathMapPager pathMappingPager) {
        if (StringUtil.isNotBlank(pathMappingPager.regex)) {
            cb.query().setRegex_Wildcard(wrapQuery(pathMappingPager.regex));
        }
        if (StringUtil.isNotBlank(pathMappingPager.replacement)) {
            cb.query().setReplacement_Wildcard(wrapQuery(pathMappingPager.replacement));
        }

 */
package org.codelibs.fess.helper;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.function.BiFunction;
import java.util.regex.Matcher;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.fess.Constants;

        return appendFileterPath(buf, escape(s));
    }

    /**
     * Escapes special regex characters in a string to create a literal pattern.
     * Handles anchor characters (^ and $) specially to preserve their regex meaning.
     *
     * @param s the string to escape
     * @return an escaped regex pattern, or empty string for comments
     */
    protected String escape(final String s) {