...
Run Format

Source file src/reflect/tostring_test.go

Documentation: reflect

  // Copyright 2009 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.
  
  // Formatting of reflection types and values for debugging.
  // Not defined as methods so they do not need to be linked into most binaries;
  // the functions are not used by the library itself, only in tests.
  
  package reflect_test
  
  import (
  	. "reflect"
  	"strconv"
  )
  
  // valueToString returns a textual representation of the reflection value val.
  // For debugging only.
  func valueToString(val Value) string {
  	var str string
  	if !val.IsValid() {
  		return "<zero Value>"
  	}
  	typ := val.Type()
  	switch val.Kind() {
  	case Int, Int8, Int16, Int32, Int64:
  		return strconv.FormatInt(val.Int(), 10)
  	case Uint, Uint8, Uint16, Uint32, Uint64, Uintptr:
  		return strconv.FormatUint(val.Uint(), 10)
  	case Float32, Float64:
  		return strconv.FormatFloat(val.Float(), 'g', -1, 64)
  	case Complex64, Complex128:
  		c := val.Complex()
  		return strconv.FormatFloat(real(c), 'g', -1, 64) + "+" + strconv.FormatFloat(imag(c), 'g', -1, 64) + "i"
  	case String:
  		return val.String()
  	case Bool:
  		if val.Bool() {
  			return "true"
  		} else {
  			return "false"
  		}
  	case Ptr:
  		v := val
  		str = typ.String() + "("
  		if v.IsNil() {
  			str += "0"
  		} else {
  			str += "&" + valueToString(v.Elem())
  		}
  		str += ")"
  		return str
  	case Array, Slice:
  		v := val
  		str += typ.String()
  		str += "{"
  		for i := 0; i < v.Len(); i++ {
  			if i > 0 {
  				str += ", "
  			}
  			str += valueToString(v.Index(i))
  		}
  		str += "}"
  		return str
  	case Map:
  		t := typ
  		str = t.String()
  		str += "{"
  		str += "<can't iterate on maps>"
  		str += "}"
  		return str
  	case Chan:
  		str = typ.String()
  		return str
  	case Struct:
  		t := typ
  		v := val
  		str += t.String()
  		str += "{"
  		for i, n := 0, v.NumField(); i < n; i++ {
  			if i > 0 {
  				str += ", "
  			}
  			str += valueToString(v.Field(i))
  		}
  		str += "}"
  		return str
  	case Interface:
  		return typ.String() + "(" + valueToString(val.Elem()) + ")"
  	case Func:
  		v := val
  		return typ.String() + "(" + strconv.FormatUint(uint64(v.Pointer()), 10) + ")"
  	default:
  		panic("valueToString: can't print type " + typ.String())
  	}
  }
  

View as plain text