} else {
		regexp.prefix, regexp.prefixComplete, regexp.prefixEnd = onePassPrefix(prog)
	}
	if regexp.prefix != "" {
		// TODO(rsc): Remove this allocation by adding
		// IndexString to package bytes.
		regexp.prefixBytes = []byte(regexp.prefix)
		regexp.prefixRune, _ = utf8.DecodeRuneInString(regexp.prefix)
	}

	n := len(prog.Inst)
	i := 0
	for matchSize[i] != 0 && matchSize[i] < n {
		i++
	}

package syntax

// Note to implementers:
// In this package, re is always a *Regexp and r is always a rune.

import (
	"slices"
	"strconv"
	"strings"
	"unicode"
)

// A Regexp is a node in a regular expression syntax tree.
type Regexp struct {
	Op       Op // operator
	Flags    Flags
	Sub      []*Regexp  // subexpressions, if any
	Sub0     [1]*Regexp // storage for short Sub

	fmt.Println(matched, err)
	matched, err = regexp.MatchString(`bar.*`, "seafood")
	fmt.Println(matched, err)
	matched, err = regexp.MatchString(`a(b`, "seafood")
	fmt.Println(matched, err)
	// Output:
	// true <nil>
	// false <nil>
	// false error parsing regexp: missing closing ): `a(b`
}

func ExampleQuoteMeta() {
	fmt.Println(regexp.QuoteMeta(`Escaping symbols like: .+*?()|[]{}^$`))

			t.Errorf("Parse(%#q, Perl): %v", regexp, err)
		}
		if re, err := Parse(regexp, POSIX); err == nil {
			t.Errorf("Parse(%#q, POSIX) = %s, should have failed", regexp, dump(re))
		}
	}
	for _, regexp := range onlyPOSIX {
		if re, err := Parse(regexp, Perl); err == nil {
			t.Errorf("Parse(%#q, Perl) = %s, should have failed", regexp, dump(re))
		}
		if _, err := Parse(regexp, POSIX); err != nil {

			WantException:  false,
		},
		{ // case 4
			Args:           strings.Split("envoy --browser=false", " "),
			ExpectedRegexp: regexp.MustCompile(".*Error: specify a pod or --selector"),
			WantException:  true,
		},
		{ // case 5
			Args:           strings.Split("envoy --browser=false pod-123456-7890", " "),
			ExpectedRegexp: regexp.MustCompile("http://localhost:3456"),
			WantException:  false,

// matches.
func repeated(res ...*regexp.Regexp) *regexp.Regexp {
	return match(group(expression(res...)).String() + `+`)
}

// group wraps the regexp in a non-capturing group.
func group(res ...*regexp.Regexp) *regexp.Regexp {
	return match(`(?:` + expression(res...).String() + `)`)
}

// capture wraps the expression in a capturing group.

package binutils

import (
	"bytes"
	"io"
	"regexp"
	"strconv"
	"strings"

	"github.com/google/pprof/internal/plugin"
	"github.com/ianlancetaylor/demangle"
)

var (
	nmOutputRE                = regexp.MustCompile(`^\s*([[:xdigit:]]+)\s+(.)\s+(.*)`)
	objdumpAsmOutputRE        = regexp.MustCompile(`^\s*([[:xdigit:]]+):\s+(.*)`)
	objdumpOutputFileLine     = regexp.MustCompile(`^;?\s?(.*):([0-9]+)`)

	if !regexp.MustCompile("SELECT \\* FROM `user`").MatchString(r.Statement.SQL.String()) {
		t.Errorf("Table with escape character, got %v", r.Statement.SQL.String())
	}

	r = dryDB.Table("user as u").Select("name").Find(&User{}).Statement
	if !regexp.MustCompile("SELECT .name. FROM user as u WHERE .u.\\..deleted_at. IS NULL").MatchString(r.Statement.SQL.String()) {

	testpoints := []struct {
		tag string
		re  *regexp.Regexp
	}{
		{
			"args",
			regexp.MustCompile(`^data file .+ GOOS=.+ GOARCH=.+ program args: .+$`),
		},
		{
			"main package",
			regexp.MustCompile(`^Package path: ` + mainPkgPath + `\s*$`),
		},
		{
			"main function",
			regexp.MustCompile(`^Func: main\s*$`),
		},
	}

	bad := false

			t.Fatal(err)
		}
		var errors []*regexp.Regexp
		for i, line := range bytes.Split(contents, []byte("\n")) {
			if bytes.HasSuffix(line, []byte("ERROR HERE")) {
				re := regexp.MustCompile(regexp.QuoteMeta(fmt.Sprintf("%s:%d:", file, i+1)))
				errors = append(errors, re)
				continue
			}

			if _, frag, ok := bytes.Cut(line, []byte("ERROR HERE: ")); ok {
				re, err := regexp.Compile(fmt.Sprintf(":%d:.*%s", i+1, frag))