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diff --git a/src/text/template/helper.go b/src/text/template/helper.go
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+// Copyright 2011 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// Helper functions to make constructing templates easier.
+
+package template
+
+import (
+	"fmt"
+	"io/fs"
+	"os"
+	"path"
+	"path/filepath"
+)
+
+// Functions and methods to parse templates.
+
+// Must is a helper that wraps a call to a function returning (*Template, error)
+// and panics if the error is non-nil. It is intended for use in variable
+// initializations such as
+//	var t = template.Must(template.New("name").Parse("text"))
+func Must(t *Template, err error) *Template {
+	if err != nil {
+		panic(err)
+	}
+	return t
+}
+
+// ParseFiles creates a new Template and parses the template definitions from
+// the named files. The returned template's name will have the base name and
+// parsed contents of the first file. There must be at least one file.
+// If an error occurs, parsing stops and the returned *Template is nil.
+//
+// When parsing multiple files with the same name in different directories,
+// the last one mentioned will be the one that results.
+// For instance, ParseFiles("a/foo", "b/foo") stores "b/foo" as the template
+// named "foo", while "a/foo" is unavailable.
+func ParseFiles(filenames ...string) (*Template, error) {
+	return parseFiles(nil, readFileOS, filenames...)
+}
+
+// ParseFiles parses the named files and associates the resulting templates with
+// t. If an error occurs, parsing stops and the returned template is nil;
+// otherwise it is t. There must be at least one file.
+// Since the templates created by ParseFiles are named by the base
+// names of the argument files, t should usually have the name of one
+// of the (base) names of the files. If it does not, depending on t's
+// contents before calling ParseFiles, t.Execute may fail. In that
+// case use t.ExecuteTemplate to execute a valid template.
+//
+// When parsing multiple files with the same name in different directories,
+// the last one mentioned will be the one that results.
+func (t *Template) ParseFiles(filenames ...string) (*Template, error) {
+	t.init()
+	return parseFiles(t, readFileOS, filenames...)
+}
+
+// parseFiles is the helper for the method and function. If the argument
+// template is nil, it is created from the first file.
+func parseFiles(t *Template, readFile func(string) (string, []byte, error), filenames ...string) (*Template, error) {
+	if len(filenames) == 0 {
+		// Not really a problem, but be consistent.
+		return nil, fmt.Errorf("template: no files named in call to ParseFiles")
+	}
+	for _, filename := range filenames {
+		name, b, err := readFile(filename)
+		if err != nil {
+			return nil, err
+		}
+		s := string(b)
+		// First template becomes return value if not already defined,
+		// and we use that one for subsequent New calls to associate
+		// all the templates together. Also, if this file has the same name
+		// as t, this file becomes the contents of t, so
+		//  t, err := New(name).Funcs(xxx).ParseFiles(name)
+		// works. Otherwise we create a new template associated with t.
+		var tmpl *Template
+		if t == nil {
+			t = New(name)
+		}
+		if name == t.Name() {
+			tmpl = t
+		} else {
+			tmpl = t.New(name)
+		}
+		_, err = tmpl.Parse(s)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return t, nil
+}
+
+// ParseGlob creates a new Template and parses the template definitions from
+// the files identified by the pattern. The files are matched according to the
+// semantics of filepath.Match, and the pattern must match at least one file.
+// The returned template will have the (base) name and (parsed) contents of the
+// first file matched by the pattern. ParseGlob is equivalent to calling
+// ParseFiles with the list of files matched by the pattern.
+//
+// When parsing multiple files with the same name in different directories,
+// the last one mentioned will be the one that results.
+func ParseGlob(pattern string) (*Template, error) {
+	return parseGlob(nil, pattern)
+}
+
+// ParseGlob parses the template definitions in the files identified by the
+// pattern and associates the resulting templates with t. The files are matched
+// according to the semantics of filepath.Match, and the pattern must match at
+// least one file. ParseGlob is equivalent to calling t.ParseFiles with the
+// list of files matched by the pattern.
+//
+// When parsing multiple files with the same name in different directories,
+// the last one mentioned will be the one that results.
+func (t *Template) ParseGlob(pattern string) (*Template, error) {
+	t.init()
+	return parseGlob(t, pattern)
+}
+
+// parseGlob is the implementation of the function and method ParseGlob.
+func parseGlob(t *Template, pattern string) (*Template, error) {
+	filenames, err := filepath.Glob(pattern)
+	if err != nil {
+		return nil, err
+	}
+	if len(filenames) == 0 {
+		return nil, fmt.Errorf("template: pattern matches no files: %#q", pattern)
+	}
+	return parseFiles(t, readFileOS, filenames...)
+}
+
+// ParseFS is like ParseFiles or ParseGlob but reads from the file system fsys
+// instead of the host operating system's file system.
+// It accepts a list of glob patterns.
+// (Note that most file names serve as glob patterns matching only themselves.)
+func ParseFS(fsys fs.FS, patterns ...string) (*Template, error) {
+	return parseFS(nil, fsys, patterns)
+}
+
+// ParseFS is like ParseFiles or ParseGlob but reads from the file system fsys
+// instead of the host operating system's file system.
+// It accepts a list of glob patterns.
+// (Note that most file names serve as glob patterns matching only themselves.)
+func (t *Template) ParseFS(fsys fs.FS, patterns ...string) (*Template, error) {
+	t.init()
+	return parseFS(t, fsys, patterns)
+}
+
+func parseFS(t *Template, fsys fs.FS, patterns []string) (*Template, error) {
+	var filenames []string
+	for _, pattern := range patterns {
+		list, err := fs.Glob(fsys, pattern)
+		if err != nil {
+			return nil, err
+		}
+		if len(list) == 0 {
+			return nil, fmt.Errorf("template: pattern matches no files: %#q", pattern)
+		}
+		filenames = append(filenames, list...)
+	}
+	return parseFiles(t, readFileFS(fsys), filenames...)
+}
+
+func readFileOS(file string) (name string, b []byte, err error) {
+	name = filepath.Base(file)
+	b, err = os.ReadFile(file)
+	return
+}
+
+func readFileFS(fsys fs.FS) func(string) (string, []byte, error) {
+	return func(file string) (name string, b []byte, err error) {
+		name = path.Base(file)
+		b, err = fs.ReadFile(fsys, file)
+		return
+	}
+}