1// Copyright 2022 The Go Authors. All rights reserved.
 2// Use of this source code is governed by a BSD-style
 3// license that can be found in the LICENSE file.
 4
 5//go:build go1.20
 6
 7package slog
 8
 9import "unsafe"
10
11type (
12	stringptr *byte // used in Value.any when the Value is a string
13	groupptr  *Attr // used in Value.any when the Value is a []Attr
14)
15
16// StringValue returns a new Value for a string.
17func StringValue(value string) Value {
18	return Value{num: uint64(len(value)), any: stringptr(unsafe.StringData(value))}
19}
20
21// GroupValue returns a new Value for a list of Attrs.
22// The caller must not subsequently mutate the argument slice.
23func GroupValue(as ...Attr) Value {
24	return Value{num: uint64(len(as)), any: groupptr(unsafe.SliceData(as))}
25}
26
27// String returns Value's value as a string, formatted like fmt.Sprint. Unlike
28// the methods Int64, Float64, and so on, which panic if v is of the
29// wrong kind, String never panics.
30func (v Value) String() string {
31	if sp, ok := v.any.(stringptr); ok {
32		return unsafe.String(sp, v.num)
33	}
34	return string(v.append(nil))
35}
36
37func (v Value) str() string {
38	return unsafe.String(v.any.(stringptr), v.num)
39}