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-rw-r--r--src/text/template/funcs.go766
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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.
+
+package template
+
+import (
+ "bytes"
+ "errors"
+ "fmt"
+ "io"
+ "net/url"
+ "reflect"
+ "strings"
+ "sync"
+ "unicode"
+ "unicode/utf8"
+)
+
+// FuncMap is the type of the map defining the mapping from names to functions.
+// Each function must have either a single return value, or two return values of
+// which the second has type error. In that case, if the second (error)
+// return value evaluates to non-nil during execution, execution terminates and
+// Execute returns that error.
+//
+// When template execution invokes a function with an argument list, that list
+// must be assignable to the function's parameter types. Functions meant to
+// apply to arguments of arbitrary type can use parameters of type interface{} or
+// of type reflect.Value. Similarly, functions meant to return a result of arbitrary
+// type can return interface{} or reflect.Value.
+type FuncMap map[string]interface{}
+
+// builtins returns the FuncMap.
+// It is not a global variable so the linker can dead code eliminate
+// more when this isn't called. See golang.org/issue/36021.
+// TODO: revert this back to a global map once golang.org/issue/2559 is fixed.
+func builtins() FuncMap {
+ return FuncMap{
+ "and": and,
+ "call": call,
+ "html": HTMLEscaper,
+ "index": index,
+ "slice": slice,
+ "js": JSEscaper,
+ "len": length,
+ "not": not,
+ "or": or,
+ "print": fmt.Sprint,
+ "printf": fmt.Sprintf,
+ "println": fmt.Sprintln,
+ "urlquery": URLQueryEscaper,
+
+ // Comparisons
+ "eq": eq, // ==
+ "ge": ge, // >=
+ "gt": gt, // >
+ "le": le, // <=
+ "lt": lt, // <
+ "ne": ne, // !=
+ }
+}
+
+var builtinFuncsOnce struct {
+ sync.Once
+ v map[string]reflect.Value
+}
+
+// builtinFuncsOnce lazily computes & caches the builtinFuncs map.
+// TODO: revert this back to a global map once golang.org/issue/2559 is fixed.
+func builtinFuncs() map[string]reflect.Value {
+ builtinFuncsOnce.Do(func() {
+ builtinFuncsOnce.v = createValueFuncs(builtins())
+ })
+ return builtinFuncsOnce.v
+}
+
+// createValueFuncs turns a FuncMap into a map[string]reflect.Value
+func createValueFuncs(funcMap FuncMap) map[string]reflect.Value {
+ m := make(map[string]reflect.Value)
+ addValueFuncs(m, funcMap)
+ return m
+}
+
+// addValueFuncs adds to values the functions in funcs, converting them to reflect.Values.
+func addValueFuncs(out map[string]reflect.Value, in FuncMap) {
+ for name, fn := range in {
+ if !goodName(name) {
+ panic(fmt.Errorf("function name %q is not a valid identifier", name))
+ }
+ v := reflect.ValueOf(fn)
+ if v.Kind() != reflect.Func {
+ panic("value for " + name + " not a function")
+ }
+ if !goodFunc(v.Type()) {
+ panic(fmt.Errorf("can't install method/function %q with %d results", name, v.Type().NumOut()))
+ }
+ out[name] = v
+ }
+}
+
+// addFuncs adds to values the functions in funcs. It does no checking of the input -
+// call addValueFuncs first.
+func addFuncs(out, in FuncMap) {
+ for name, fn := range in {
+ out[name] = fn
+ }
+}
+
+// goodFunc reports whether the function or method has the right result signature.
+func goodFunc(typ reflect.Type) bool {
+ // We allow functions with 1 result or 2 results where the second is an error.
+ switch {
+ case typ.NumOut() == 1:
+ return true
+ case typ.NumOut() == 2 && typ.Out(1) == errorType:
+ return true
+ }
+ return false
+}
+
+// goodName reports whether the function name is a valid identifier.
+func goodName(name string) bool {
+ if name == "" {
+ return false
+ }
+ for i, r := range name {
+ switch {
+ case r == '_':
+ case i == 0 && !unicode.IsLetter(r):
+ return false
+ case !unicode.IsLetter(r) && !unicode.IsDigit(r):
+ return false
+ }
+ }
+ return true
+}
+
+// findFunction looks for a function in the template, and global map.
+func findFunction(name string, tmpl *Template) (reflect.Value, bool) {
+ if tmpl != nil && tmpl.common != nil {
+ tmpl.muFuncs.RLock()
+ defer tmpl.muFuncs.RUnlock()
+ if fn := tmpl.execFuncs[name]; fn.IsValid() {
+ return fn, true
+ }
+ }
+ if fn := builtinFuncs()[name]; fn.IsValid() {
+ return fn, true
+ }
+ return reflect.Value{}, false
+}
+
+// prepareArg checks if value can be used as an argument of type argType, and
+// converts an invalid value to appropriate zero if possible.
+func prepareArg(value reflect.Value, argType reflect.Type) (reflect.Value, error) {
+ if !value.IsValid() {
+ if !canBeNil(argType) {
+ return reflect.Value{}, fmt.Errorf("value is nil; should be of type %s", argType)
+ }
+ value = reflect.Zero(argType)
+ }
+ if value.Type().AssignableTo(argType) {
+ return value, nil
+ }
+ if intLike(value.Kind()) && intLike(argType.Kind()) && value.Type().ConvertibleTo(argType) {
+ value = value.Convert(argType)
+ return value, nil
+ }
+ return reflect.Value{}, fmt.Errorf("value has type %s; should be %s", value.Type(), argType)
+}
+
+func intLike(typ reflect.Kind) bool {
+ switch typ {
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return true
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return true
+ }
+ return false
+}
+
+// indexArg checks if a reflect.Value can be used as an index, and converts it to int if possible.
+func indexArg(index reflect.Value, cap int) (int, error) {
+ var x int64
+ switch index.Kind() {
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ x = index.Int()
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ x = int64(index.Uint())
+ case reflect.Invalid:
+ return 0, fmt.Errorf("cannot index slice/array with nil")
+ default:
+ return 0, fmt.Errorf("cannot index slice/array with type %s", index.Type())
+ }
+ if x < 0 || int(x) < 0 || int(x) > cap {
+ return 0, fmt.Errorf("index out of range: %d", x)
+ }
+ return int(x), nil
+}
+
+// Indexing.
+
+// index returns the result of indexing its first argument by the following
+// arguments. Thus "index x 1 2 3" is, in Go syntax, x[1][2][3]. Each
+// indexed item must be a map, slice, or array.
+func index(item reflect.Value, indexes ...reflect.Value) (reflect.Value, error) {
+ item = indirectInterface(item)
+ if !item.IsValid() {
+ return reflect.Value{}, fmt.Errorf("index of untyped nil")
+ }
+ for _, index := range indexes {
+ index = indirectInterface(index)
+ var isNil bool
+ if item, isNil = indirect(item); isNil {
+ return reflect.Value{}, fmt.Errorf("index of nil pointer")
+ }
+ switch item.Kind() {
+ case reflect.Array, reflect.Slice, reflect.String:
+ x, err := indexArg(index, item.Len())
+ if err != nil {
+ return reflect.Value{}, err
+ }
+ item = item.Index(x)
+ case reflect.Map:
+ index, err := prepareArg(index, item.Type().Key())
+ if err != nil {
+ return reflect.Value{}, err
+ }
+ if x := item.MapIndex(index); x.IsValid() {
+ item = x
+ } else {
+ item = reflect.Zero(item.Type().Elem())
+ }
+ case reflect.Invalid:
+ // the loop holds invariant: item.IsValid()
+ panic("unreachable")
+ default:
+ return reflect.Value{}, fmt.Errorf("can't index item of type %s", item.Type())
+ }
+ }
+ return item, nil
+}
+
+// Slicing.
+
+// slice returns the result of slicing its first argument by the remaining
+// arguments. Thus "slice x 1 2" is, in Go syntax, x[1:2], while "slice x"
+// is x[:], "slice x 1" is x[1:], and "slice x 1 2 3" is x[1:2:3]. The first
+// argument must be a string, slice, or array.
+func slice(item reflect.Value, indexes ...reflect.Value) (reflect.Value, error) {
+ item = indirectInterface(item)
+ if !item.IsValid() {
+ return reflect.Value{}, fmt.Errorf("slice of untyped nil")
+ }
+ if len(indexes) > 3 {
+ return reflect.Value{}, fmt.Errorf("too many slice indexes: %d", len(indexes))
+ }
+ var cap int
+ switch item.Kind() {
+ case reflect.String:
+ if len(indexes) == 3 {
+ return reflect.Value{}, fmt.Errorf("cannot 3-index slice a string")
+ }
+ cap = item.Len()
+ case reflect.Array, reflect.Slice:
+ cap = item.Cap()
+ default:
+ return reflect.Value{}, fmt.Errorf("can't slice item of type %s", item.Type())
+ }
+ // set default values for cases item[:], item[i:].
+ idx := [3]int{0, item.Len()}
+ for i, index := range indexes {
+ x, err := indexArg(index, cap)
+ if err != nil {
+ return reflect.Value{}, err
+ }
+ idx[i] = x
+ }
+ // given item[i:j], make sure i <= j.
+ if idx[0] > idx[1] {
+ return reflect.Value{}, fmt.Errorf("invalid slice index: %d > %d", idx[0], idx[1])
+ }
+ if len(indexes) < 3 {
+ return item.Slice(idx[0], idx[1]), nil
+ }
+ // given item[i:j:k], make sure i <= j <= k.
+ if idx[1] > idx[2] {
+ return reflect.Value{}, fmt.Errorf("invalid slice index: %d > %d", idx[1], idx[2])
+ }
+ return item.Slice3(idx[0], idx[1], idx[2]), nil
+}
+
+// Length
+
+// length returns the length of the item, with an error if it has no defined length.
+func length(item reflect.Value) (int, error) {
+ item, isNil := indirect(item)
+ if isNil {
+ return 0, fmt.Errorf("len of nil pointer")
+ }
+ switch item.Kind() {
+ case reflect.Array, reflect.Chan, reflect.Map, reflect.Slice, reflect.String:
+ return item.Len(), nil
+ }
+ return 0, fmt.Errorf("len of type %s", item.Type())
+}
+
+// Function invocation
+
+// call returns the result of evaluating the first argument as a function.
+// The function must return 1 result, or 2 results, the second of which is an error.
+func call(fn reflect.Value, args ...reflect.Value) (reflect.Value, error) {
+ fn = indirectInterface(fn)
+ if !fn.IsValid() {
+ return reflect.Value{}, fmt.Errorf("call of nil")
+ }
+ typ := fn.Type()
+ if typ.Kind() != reflect.Func {
+ return reflect.Value{}, fmt.Errorf("non-function of type %s", typ)
+ }
+ if !goodFunc(typ) {
+ return reflect.Value{}, fmt.Errorf("function called with %d args; should be 1 or 2", typ.NumOut())
+ }
+ numIn := typ.NumIn()
+ var dddType reflect.Type
+ if typ.IsVariadic() {
+ if len(args) < numIn-1 {
+ return reflect.Value{}, fmt.Errorf("wrong number of args: got %d want at least %d", len(args), numIn-1)
+ }
+ dddType = typ.In(numIn - 1).Elem()
+ } else {
+ if len(args) != numIn {
+ return reflect.Value{}, fmt.Errorf("wrong number of args: got %d want %d", len(args), numIn)
+ }
+ }
+ argv := make([]reflect.Value, len(args))
+ for i, arg := range args {
+ arg = indirectInterface(arg)
+ // Compute the expected type. Clumsy because of variadics.
+ argType := dddType
+ if !typ.IsVariadic() || i < numIn-1 {
+ argType = typ.In(i)
+ }
+
+ var err error
+ if argv[i], err = prepareArg(arg, argType); err != nil {
+ return reflect.Value{}, fmt.Errorf("arg %d: %s", i, err)
+ }
+ }
+ return safeCall(fn, argv)
+}
+
+// safeCall runs fun.Call(args), and returns the resulting value and error, if
+// any. If the call panics, the panic value is returned as an error.
+func safeCall(fun reflect.Value, args []reflect.Value) (val reflect.Value, err error) {
+ defer func() {
+ if r := recover(); r != nil {
+ if e, ok := r.(error); ok {
+ err = e
+ } else {
+ err = fmt.Errorf("%v", r)
+ }
+ }
+ }()
+ ret := fun.Call(args)
+ if len(ret) == 2 && !ret[1].IsNil() {
+ return ret[0], ret[1].Interface().(error)
+ }
+ return ret[0], nil
+}
+
+// Boolean logic.
+
+func truth(arg reflect.Value) bool {
+ t, _ := isTrue(indirectInterface(arg))
+ return t
+}
+
+// and computes the Boolean AND of its arguments, returning
+// the first false argument it encounters, or the last argument.
+func and(arg0 reflect.Value, args ...reflect.Value) reflect.Value {
+ if !truth(arg0) {
+ return arg0
+ }
+ for i := range args {
+ arg0 = args[i]
+ if !truth(arg0) {
+ break
+ }
+ }
+ return arg0
+}
+
+// or computes the Boolean OR of its arguments, returning
+// the first true argument it encounters, or the last argument.
+func or(arg0 reflect.Value, args ...reflect.Value) reflect.Value {
+ if truth(arg0) {
+ return arg0
+ }
+ for i := range args {
+ arg0 = args[i]
+ if truth(arg0) {
+ break
+ }
+ }
+ return arg0
+}
+
+// not returns the Boolean negation of its argument.
+func not(arg reflect.Value) bool {
+ return !truth(arg)
+}
+
+// Comparison.
+
+// TODO: Perhaps allow comparison between signed and unsigned integers.
+
+var (
+ errBadComparisonType = errors.New("invalid type for comparison")
+ errBadComparison = errors.New("incompatible types for comparison")
+ errNoComparison = errors.New("missing argument for comparison")
+)
+
+type kind int
+
+const (
+ invalidKind kind = iota
+ boolKind
+ complexKind
+ intKind
+ floatKind
+ stringKind
+ uintKind
+)
+
+func basicKind(v reflect.Value) (kind, error) {
+ switch v.Kind() {
+ case reflect.Bool:
+ return boolKind, nil
+ case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+ return intKind, nil
+ case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uintptr:
+ return uintKind, nil
+ case reflect.Float32, reflect.Float64:
+ return floatKind, nil
+ case reflect.Complex64, reflect.Complex128:
+ return complexKind, nil
+ case reflect.String:
+ return stringKind, nil
+ }
+ return invalidKind, errBadComparisonType
+}
+
+// eq evaluates the comparison a == b || a == c || ...
+func eq(arg1 reflect.Value, arg2 ...reflect.Value) (bool, error) {
+ arg1 = indirectInterface(arg1)
+ if arg1 != zero {
+ if t1 := arg1.Type(); !t1.Comparable() {
+ return false, fmt.Errorf("uncomparable type %s: %v", t1, arg1)
+ }
+ }
+ if len(arg2) == 0 {
+ return false, errNoComparison
+ }
+ k1, _ := basicKind(arg1)
+ for _, arg := range arg2 {
+ arg = indirectInterface(arg)
+ k2, _ := basicKind(arg)
+ truth := false
+ if k1 != k2 {
+ // Special case: Can compare integer values regardless of type's sign.
+ switch {
+ case k1 == intKind && k2 == uintKind:
+ truth = arg1.Int() >= 0 && uint64(arg1.Int()) == arg.Uint()
+ case k1 == uintKind && k2 == intKind:
+ truth = arg.Int() >= 0 && arg1.Uint() == uint64(arg.Int())
+ default:
+ return false, errBadComparison
+ }
+ } else {
+ switch k1 {
+ case boolKind:
+ truth = arg1.Bool() == arg.Bool()
+ case complexKind:
+ truth = arg1.Complex() == arg.Complex()
+ case floatKind:
+ truth = arg1.Float() == arg.Float()
+ case intKind:
+ truth = arg1.Int() == arg.Int()
+ case stringKind:
+ truth = arg1.String() == arg.String()
+ case uintKind:
+ truth = arg1.Uint() == arg.Uint()
+ default:
+ if arg == zero {
+ truth = arg1 == arg
+ } else {
+ if t2 := arg.Type(); !t2.Comparable() {
+ return false, fmt.Errorf("uncomparable type %s: %v", t2, arg)
+ }
+ truth = arg1.Interface() == arg.Interface()
+ }
+ }
+ }
+ if truth {
+ return true, nil
+ }
+ }
+ return false, nil
+}
+
+// ne evaluates the comparison a != b.
+func ne(arg1, arg2 reflect.Value) (bool, error) {
+ // != is the inverse of ==.
+ equal, err := eq(arg1, arg2)
+ return !equal, err
+}
+
+// lt evaluates the comparison a < b.
+func lt(arg1, arg2 reflect.Value) (bool, error) {
+ arg1 = indirectInterface(arg1)
+ k1, err := basicKind(arg1)
+ if err != nil {
+ return false, err
+ }
+ arg2 = indirectInterface(arg2)
+ k2, err := basicKind(arg2)
+ if err != nil {
+ return false, err
+ }
+ truth := false
+ if k1 != k2 {
+ // Special case: Can compare integer values regardless of type's sign.
+ switch {
+ case k1 == intKind && k2 == uintKind:
+ truth = arg1.Int() < 0 || uint64(arg1.Int()) < arg2.Uint()
+ case k1 == uintKind && k2 == intKind:
+ truth = arg2.Int() >= 0 && arg1.Uint() < uint64(arg2.Int())
+ default:
+ return false, errBadComparison
+ }
+ } else {
+ switch k1 {
+ case boolKind, complexKind:
+ return false, errBadComparisonType
+ case floatKind:
+ truth = arg1.Float() < arg2.Float()
+ case intKind:
+ truth = arg1.Int() < arg2.Int()
+ case stringKind:
+ truth = arg1.String() < arg2.String()
+ case uintKind:
+ truth = arg1.Uint() < arg2.Uint()
+ default:
+ panic("invalid kind")
+ }
+ }
+ return truth, nil
+}
+
+// le evaluates the comparison <= b.
+func le(arg1, arg2 reflect.Value) (bool, error) {
+ // <= is < or ==.
+ lessThan, err := lt(arg1, arg2)
+ if lessThan || err != nil {
+ return lessThan, err
+ }
+ return eq(arg1, arg2)
+}
+
+// gt evaluates the comparison a > b.
+func gt(arg1, arg2 reflect.Value) (bool, error) {
+ // > is the inverse of <=.
+ lessOrEqual, err := le(arg1, arg2)
+ if err != nil {
+ return false, err
+ }
+ return !lessOrEqual, nil
+}
+
+// ge evaluates the comparison a >= b.
+func ge(arg1, arg2 reflect.Value) (bool, error) {
+ // >= is the inverse of <.
+ lessThan, err := lt(arg1, arg2)
+ if err != nil {
+ return false, err
+ }
+ return !lessThan, nil
+}
+
+// HTML escaping.
+
+var (
+ htmlQuot = []byte("&#34;") // shorter than "&quot;"
+ htmlApos = []byte("&#39;") // shorter than "&apos;" and apos was not in HTML until HTML5
+ htmlAmp = []byte("&amp;")
+ htmlLt = []byte("&lt;")
+ htmlGt = []byte("&gt;")
+ htmlNull = []byte("\uFFFD")
+)
+
+// HTMLEscape writes to w the escaped HTML equivalent of the plain text data b.
+func HTMLEscape(w io.Writer, b []byte) {
+ last := 0
+ for i, c := range b {
+ var html []byte
+ switch c {
+ case '\000':
+ html = htmlNull
+ case '"':
+ html = htmlQuot
+ case '\'':
+ html = htmlApos
+ case '&':
+ html = htmlAmp
+ case '<':
+ html = htmlLt
+ case '>':
+ html = htmlGt
+ default:
+ continue
+ }
+ w.Write(b[last:i])
+ w.Write(html)
+ last = i + 1
+ }
+ w.Write(b[last:])
+}
+
+// HTMLEscapeString returns the escaped HTML equivalent of the plain text data s.
+func HTMLEscapeString(s string) string {
+ // Avoid allocation if we can.
+ if !strings.ContainsAny(s, "'\"&<>\000") {
+ return s
+ }
+ var b bytes.Buffer
+ HTMLEscape(&b, []byte(s))
+ return b.String()
+}
+
+// HTMLEscaper returns the escaped HTML equivalent of the textual
+// representation of its arguments.
+func HTMLEscaper(args ...interface{}) string {
+ return HTMLEscapeString(evalArgs(args))
+}
+
+// JavaScript escaping.
+
+var (
+ jsLowUni = []byte(`\u00`)
+ hex = []byte("0123456789ABCDEF")
+
+ jsBackslash = []byte(`\\`)
+ jsApos = []byte(`\'`)
+ jsQuot = []byte(`\"`)
+ jsLt = []byte(`\u003C`)
+ jsGt = []byte(`\u003E`)
+ jsAmp = []byte(`\u0026`)
+ jsEq = []byte(`\u003D`)
+)
+
+// JSEscape writes to w the escaped JavaScript equivalent of the plain text data b.
+func JSEscape(w io.Writer, b []byte) {
+ last := 0
+ for i := 0; i < len(b); i++ {
+ c := b[i]
+
+ if !jsIsSpecial(rune(c)) {
+ // fast path: nothing to do
+ continue
+ }
+ w.Write(b[last:i])
+
+ if c < utf8.RuneSelf {
+ // Quotes, slashes and angle brackets get quoted.
+ // Control characters get written as \u00XX.
+ switch c {
+ case '\\':
+ w.Write(jsBackslash)
+ case '\'':
+ w.Write(jsApos)
+ case '"':
+ w.Write(jsQuot)
+ case '<':
+ w.Write(jsLt)
+ case '>':
+ w.Write(jsGt)
+ case '&':
+ w.Write(jsAmp)
+ case '=':
+ w.Write(jsEq)
+ default:
+ w.Write(jsLowUni)
+ t, b := c>>4, c&0x0f
+ w.Write(hex[t : t+1])
+ w.Write(hex[b : b+1])
+ }
+ } else {
+ // Unicode rune.
+ r, size := utf8.DecodeRune(b[i:])
+ if unicode.IsPrint(r) {
+ w.Write(b[i : i+size])
+ } else {
+ fmt.Fprintf(w, "\\u%04X", r)
+ }
+ i += size - 1
+ }
+ last = i + 1
+ }
+ w.Write(b[last:])
+}
+
+// JSEscapeString returns the escaped JavaScript equivalent of the plain text data s.
+func JSEscapeString(s string) string {
+ // Avoid allocation if we can.
+ if strings.IndexFunc(s, jsIsSpecial) < 0 {
+ return s
+ }
+ var b bytes.Buffer
+ JSEscape(&b, []byte(s))
+ return b.String()
+}
+
+func jsIsSpecial(r rune) bool {
+ switch r {
+ case '\\', '\'', '"', '<', '>', '&', '=':
+ return true
+ }
+ return r < ' ' || utf8.RuneSelf <= r
+}
+
+// JSEscaper returns the escaped JavaScript equivalent of the textual
+// representation of its arguments.
+func JSEscaper(args ...interface{}) string {
+ return JSEscapeString(evalArgs(args))
+}
+
+// URLQueryEscaper returns the escaped value of the textual representation of
+// its arguments in a form suitable for embedding in a URL query.
+func URLQueryEscaper(args ...interface{}) string {
+ return url.QueryEscape(evalArgs(args))
+}
+
+// evalArgs formats the list of arguments into a string. It is therefore equivalent to
+// fmt.Sprint(args...)
+// except that each argument is indirected (if a pointer), as required,
+// using the same rules as the default string evaluation during template
+// execution.
+func evalArgs(args []interface{}) string {
+ ok := false
+ var s string
+ // Fast path for simple common case.
+ if len(args) == 1 {
+ s, ok = args[0].(string)
+ }
+ if !ok {
+ for i, arg := range args {
+ a, ok := printableValue(reflect.ValueOf(arg))
+ if ok {
+ args[i] = a
+ } // else let fmt do its thing
+ }
+ s = fmt.Sprint(args...)
+ }
+ return s
+}