golang.org/x/exp@v0.0.0-20240506185415-9bf2ced13842/slog/value_120.go (about)

     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  
     7  package slog
     8  
     9  import "unsafe"
    10  
    11  type (
    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.
    17  func 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.
    23  func 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.
    30  func (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  
    37  func (v Value) str() string {
    38  	return unsafe.String(v.any.(stringptr), v.num)
    39  }