feat implements proxy interface #2

README.md

@@ -146,14 +146,16 @@ The function `Execute()` executes the command. See the section
 setting.Execute()
 ```
 
-### Shadow
+### Proxy
 
-The shadow structure is used to copy the values of the flags to the
-shadow structure. The shadow structure is set using the `SetShadow()`
-and configured using the tag `shadow`.
+The proxy structure is used to copy the values of the flags to the
+proxy structure. The proxy structure is used to access the values of the
+flags.
+
+The proxy structure must implement the `Proxy` interface.
 
 ```go
-type Shadow struct {
+type MyObj struct {
   Verbose bool
   Serve   struct {
     Host string
@@ -161,12 +163,14 @@ type Shadow struct {
   }
 }
 
+func (m *MyObj) Copy(_ map[string]any) {
+}
+
 func main() {
   setting := New(os.Args[0], Definition{})
-  setting.SetShadow(Shadow{})
+  setting.SetProxy(&MyObj{})
   setting.Parse(os.Args[1:])
   setting.Execute()
-  fmt.Printf("Shadow: %+v", setting.GetShadow())
 }
 ```
 

api.go

@@ -12,18 +12,22 @@ import (
 	"reflect"
 )
 
-// ExecuteWithShadow executes the command line arguments and calls the functions.
-func ExecuteWithShadow[C any, D Copyable[D]](cmd C, cnf D) *Settings[C] {
-	return execute(cmd, cnf, os.Args[0], os.Args[1:])
-}
-
-type noShadow struct{}
+type dummyCopyArg struct{}
 
-func (n noShadow) Copy(a noShadow) {}
+func (n dummyCopyArg) Copy(_ map[string]any) {}
 
 // Execute executes the command line arguments and calls the functions.
-func Execute[C any](cmd C) *Settings[C] {
-	return execute(cmd, noShadow{}, os.Args[0], os.Args[1:])
+func Execute[C any](cmd C, cpy ...Proxy) *Settings[C] {
+
+	if cpy == nil {
+		return execute(cmd, dummyCopyArg{}, os.Args[0], os.Args[1:])
+	}
+
+	if len(cpy) > 1 {
+		panic("too many arguments")
+	}
+
+	return execute(cmd, cpy[0], os.Args[0], os.Args[1:])
 }
 
 // PrintFlagOutput prints the flag output to the standard output.
@@ -36,15 +40,15 @@ func (s *Settings[C]) GetFlagOutput() {
 	fmt.Println(s.command.flagSet.Output())
 }
 
-// execute is the internal implementation of ExecuteWithShadow.
-func execute[C any, D Copyable[D]](cmd C, cnf D, name string, args []string) *Settings[C] {
+// execute is the internal implementation of Execute.
+func execute[C any, D Proxy](cmd C, proxy D, name string, args []string) *Settings[C] {
 	instance := New(name, cmd)
 	if instance.HasErrors() {
 		return instance
 	}
 
-	if (reflect.ValueOf(&cnf).Elem().Type() != reflect.TypeOf(noShadow{})) {
-		instance.SetShadow(cnf)
+	if (reflect.ValueOf(&proxy).Elem().Type() != reflect.TypeOf(dummyCopyArg{})) {
+		instance.SetProxy(proxy)
 		if instance.HasErrors() {
 			return instance
 		}
@@ -59,10 +63,6 @@ func execute[C any, D Copyable[D]](cmd C, cnf D, name string, args []string) *Se
 		return instance
 	}
 
-	if instance.shadow != nil {
-		cnf.Copy(instance.shadow.(D))
-	}
-
 	instance.Execute()
 	if instance.HasErrors() {
 		return instance
@@ -87,6 +87,8 @@ func New[C any](name string, definitions C) *Settings[C] {
 		return s
 	}
 
+	s.mapping = make(map[string]any)
+
 	buf := bytes.NewBufferString("")
 	s.flagOutput = io.Writer(buf)
 	s.definitions = definitions

api_test.go

@@ -25,7 +25,7 @@ func TestUsage(t *testing.T) {
 type TestDataStruct struct {
 }
 
-func (s *TestDataStruct) Copy(x *TestDataStruct) {
+func (s *TestDataStruct) Copy(_ map[string]any) {
 
 }
 
@@ -44,8 +44,7 @@ func TestExecuteTypeStringIsNotSupported(t *testing.T) {
 
 func TestExecuteHelp(t *testing.T) {
 	instance := execute(CmdTest1{}, &TestDataStruct{}, "test", []string{"-h"})
-	assert.False(t, instance.HasErrors())
-
+	assert.True(t, instance.HelpRequested())
 }
 
 func TestNewIntWithError(t *testing.T) {

command.go

@@ -12,7 +12,6 @@ type cmd[C any] struct {
 	name         string
 	flagSet      *flag.FlagSet
 	tagMapping   map[string]string
-	shadowMapping map[string]string
 	commands     []*cmd[C]
 	settings     *Settings[C]
 	valuePath    []string
@@ -61,7 +60,6 @@ func buildCommandStruct[C any](s *Settings[C], name, fkt string, errorHandling f
 		commands:     []*cmd[C]{},
 		settings:     s,
 		tagMapping:   map[string]string{},
-		shadowMapping: map[string]string{},
 		valuePath:    path,
 		functionName: fkt,
 	}
@@ -157,15 +155,8 @@ func (c *cmd[C]) parseStruct(dta any) {
 			if m[tagLong] != "" {
 				c.tagMapping[m[tagLong]] = v.Type().Field(i).Name
 			}
-
-			if m[tagShadow] != "" {
-				c.shadowMapping[v.Type().Field(i).Name] = m[tagShadow]
-			}
-
 			c.initFlags(x, m)
 		} else if m[tagCommand] != "" {
-
-			//c.valuePath = append(c.valuePath, )
 			c.tagMapping[m[tagCommand]] = v.Type().Field(i).Name
 
 			c.initCommands(x, m, v.Type().Field(i).Name)

error.go

@@ -126,3 +126,9 @@ type MissingFunctionError error
 func newMissingFunctionError(missing string) MissingFunctionError {
 	return MissingFunctionError(errors.New("missing function " + missing))
 }
+
+type InvalidTypeForPathError error
+
+func newInvalidTypeForPathError(path string, pt string, nt string) InvalidTypeForPathError {
+	return InvalidTypeForPathError(errors.New("invalid type for path " + path + ": expected " + pt + ", got " + nt))
+}

error_test.go

@@ -96,3 +96,9 @@ func TestMissingFunctionError(t *testing.T) {
 	_, ok := err.(MissingFunctionError)
 	assert.True(t, ok)
 }
+
+func TestInvalidTypeForPathError(t *testing.T) {
+	err := newInvalidTypeForPathError("test", "test", "test")
+	_, ok := err.(InvalidTypeForPathError)
+	assert.True(t, ok)
+}

execute.go

@@ -6,8 +6,10 @@ package xflags
 import (
 	"flag"
 	"fmt"
+	"github.com/stretchr/testify/assert"
 	"reflect"
 	"strings"
+	"testing"
 )
 
 func (s *Settings[C]) Execute() *Settings[C] {
@@ -31,7 +33,6 @@ func (s *Settings[C]) Execute() *Settings[C] {
 
 func callCmdFunctions[C any](settings *Settings[C], commands []*cmd[C]) bool {
 
-	//result := false
 	wasExecuted := false
 	shouldExecute := false
 
@@ -117,3 +118,33 @@ func (s *Settings[C]) MissingCommand() bool {
 func (s *Settings[C]) WasExecuted() bool {
 	return s.wasExecuted
 }
+
+func TestWrongDefinitionType(t *testing.T) {
+	c := New("root", 2)
+	c.Parse([]string{"test"})
+	c.Execute()
+	assert.True(t, c.HasErrors())
+}
+
+type testExecuteCommandStruct struct {
+	Command1 struct {
+	} `command:"command1" description:"Command 1" callback:"command1Callback" `
+	Command2 struct {
+		Command3 struct {
+		} `command:"command3" description:"Command 3" callback:"command3Callback" call:"DoCmd3"`
+	} `command:"command2" description:"Command 2" callback:"command2Callback" `
+}
+
+func (c *testExecuteCommandStruct) DoCmd3(s *Settings[testExecuteCommandStruct]) {
+}
+
+func (c *testExecuteCommandStruct) command1Callback(args []string) {
+	fmt.Println("command1Callback", args)
+}
+
+func TestExecute1(t *testing.T) {
+	c := New("root", testExecuteCommandStruct{})
+	c.Parse([]string{"command2", "command3", "commandX"})
+	c.Execute()
+	assert.False(t, c.HasErrors())
+}

flag.go

-// Copyright 2022 schukai GmbH
-// SPDX-License-Identifier: AGPL-3.0
-
-package xflags

flag_test.go

-// Copyright 2022 schukai GmbH
-// SPDX-License-Identifier: AGPL-3.0
-
-package xflags
-
-import (
-	"fmt"
-	"github.com/stretchr/testify/assert"
-	"testing"
-)
-
-func TestWrongDefinitionType(t *testing.T) {
-	c := New("root", 2)
-	c.Parse([]string{"test"})
-	c.Execute()
-	assert.True(t, c.HasErrors())
-}
-
-type testExecuteCommandStruct struct {
-	Command1 struct {
-	} `command:"command1" description:"Command 1" callback:"command1Callback" `
-	Command2 struct {
-		Command3 struct {
-		} `command:"command3" description:"Command 3" callback:"command3Callback" call:"DoCmd3"`
-	} `command:"command2" description:"Command 2" callback:"command2Callback" `
-}
-
-func (c *testExecuteCommandStruct) DoCmd3(s *Settings[testExecuteCommandStruct]) {
-}
-
-func (c *testExecuteCommandStruct) command1Callback(args []string) {
-	fmt.Println("command1Callback", args)
-}
-
-func TestExecute1(t *testing.T) {
-	c := New("root", testExecuteCommandStruct{})
-	c.Parse([]string{"command2", "command3", "commandX"})
-	c.Execute()
-	assert.False(t, c.HasErrors())
-}

issue-1_test.go

@@ -60,7 +60,7 @@ func TestIssue1TestCallCMD4(tp *testing.T) {
 
 	for i, tt := range testData {
 		tp.Run(strconv.Itoa(i)+":"+strings.Join(tt.args, ","), func(t *testing.T) {
-			s := execute(testCmdStructIssue1{}, noShadow{}, "test", tt.args)
+			s := execute(testCmdStructIssue1{}, dummyCopyArg{}, "test", tt.args)
 			assert.Equal(t, tt.hasErrors, s.HasErrors())
 			assert.Equal(t, tt.hasHint, s.HasHint())
 
@@ -75,27 +75,27 @@ func TestIssue1TestCallCMD4(tp *testing.T) {
 }
 
 func TestIssue1TestNoCallback(t *testing.T) {
-	s := execute(testCmdStructIssue1{}, noShadow{}, "test", []string{"cmd1", "cmd6", "cmd7"})
+	s := execute(testCmdStructIssue1{}, dummyCopyArg{}, "test", []string{"cmd1", "cmd6", "cmd7"})
 	assert.Equal(t, 3, len(s.Errors()))
 	assert.False(t, s.WasExecuted())
 }
 
 func TestIssue1TestToMuchCommands(t *testing.T) {
-	s := execute(testCmdStructIssue1{}, noShadow{}, "test", []string{"cmd1", "cmd9"})
+	s := execute(testCmdStructIssue1{}, dummyCopyArg{}, "test", []string{"cmd1", "cmd9"})
 	assert.True(t, s.MissingCommand())
 	assert.False(t, s.WasExecuted())
 }
 
 // here it is tested whether the last and defined callback is called
 func TestIssue1TestCallCMD3(t *testing.T) {
-	s := execute(testCmdStructIssue1{}, noShadow{}, "test", []string{"cmd1", "cmd2", "cmd3"})
+	s := execute(testCmdStructIssue1{}, dummyCopyArg{}, "test", []string{"cmd1", "cmd2", "cmd3"})
 	assert.Equal(t, 0, len(s.Errors()))
 	assert.True(t, s.WasExecuted())
 }
 
 // NoShadow is an internal Struct for testing
 func TestIssue1MessageWithNoShadow(t *testing.T) {
-	s := execute(testCmdStructIssue1{}, noShadow{}, "test", []string{"cmd1", "cmd2", "cmd3", "-v3"})
+	s := execute(testCmdStructIssue1{}, dummyCopyArg{}, "test", []string{"cmd1", "cmd2", "cmd3", "-v3"})
 	assert.Equal(t, 0, len(s.Errors()))
 }
 
@@ -139,7 +139,7 @@ func TestIssue1Summary(tp *testing.T) {
 	for _, tt := range data {
 		tp.Run(tt.args[0], func(t *testing.T) {
 
-			s := execute(testCmdStructIssue1{}, noShadow{}, "test", tt.args)
+			s := execute(testCmdStructIssue1{}, dummyCopyArg{}, "test", tt.args)
 			assert.Equal(t, tt.helpRequested, s.HelpRequested())
 			assert.Equal(t, tt.wasExecuted, s.WasExecuted())
 			assert.Equal(t, tt.missingCommand, s.MissingCommand())

shadow.go → mapping.go

@@ -9,25 +9,26 @@ import (
 	"strings"
 )
 
-// SetShadow sets the shadow struct for the flag configuration.
-func (s *Settings[C]) SetShadow(shadow any) *Settings[C] {
+// SetProxy sets the shadow struct for the flag configuration.
+func (s *Settings[C]) SetProxy(proxy Proxy) *Settings[C] {
 
-	if reflect.TypeOf(shadow).Kind() != reflect.Ptr {
+	if reflect.TypeOf(proxy).Kind() != reflect.Ptr {
 		s.errors = append(s.errors, ShadowMustBePointerError)
 		return s
 	}
 
-	if reflect.TypeOf(shadow).Elem().Kind() != reflect.Struct {
+	if reflect.TypeOf(proxy).Elem().Kind() != reflect.Struct {
 		s.errors = append(s.errors, ShadowMustBePointerError)
 		return s
 	}
 
-	s.shadow = shadow
+	s.proxy = proxy
 	return s
 }
 
-type Copyable[C any] interface {
-	Copy(data C)
+// Proxy is the interface for the proxy struct.
+type Proxy interface {
+	Copy(map[string]any)
 }
 
 func (s *Settings[C]) assignValues(c cmd[C]) {
@@ -46,33 +47,15 @@ func (s *Settings[C]) assignValues(c cmd[C]) {
 		pa := append(c.valuePath, k)
 		p := strings.Join(pa, ".")
 
-		err := setValueUsingPath(&s.definitions, p, value)
+		err := SetValueUsingPath(&s.definitions, p, value)
 		if err != nil {
 			s.errors = append(s.errors, err)
 		}
 
-		err = c.setShadowValue(s.shadow, k, value)
-		if err != nil {
-			s.errors = append(s.errors, err)
-		}
+		s.mapping[p] = value
 
 		return
 
 	})
 
 }
-
-func (c cmd[C]) setShadowValue(obj any, k string, value string) error {
-
-	if obj == nil {
-		return nil
-	}
-
-	// set shadow
-	n, ok := c.shadowMapping[k]
-	if !ok {
-		return nil
-	}
-
-	return setValueUsingPath(obj, n, value)
-}

shadow_test.go → mapping_test.go

@@ -20,13 +20,6 @@ type ConfigStruct6 struct {
 	ValSub           ConfigStruct6Sub1
 }
 
-func TestFlagSetShadowError(t *testing.T) {
-	settings := New("test", testExecutionStruct{})
-	settings.SetShadow(3)
-	assert.True(t, settings.HasErrors())
-
-}
-
 func TestFlagCopyToShadow(t *testing.T) {
 
 	c := ConfigStruct6{}
@@ -35,7 +28,7 @@ func TestFlagCopyToShadow(t *testing.T) {
 	settings := New("test", testExecutionStruct{})
 	assert.NotNil(t, settings)
 
-	settings.SetShadow(&c)
+	settings.SetProxy(&c)
 	assert.False(t, settings.HasErrors())
 
 	settings.Parse([]string{"-a", "command1", "-d"})
@@ -45,8 +38,9 @@ func TestFlagCopyToShadow(t *testing.T) {
 
 }
 
-func (s *ConfigStruct6) Copy(p *ConfigStruct6) {
-
+func (s *ConfigStruct6) Copy(m map[string]any) {
+	SetValueUsingPath(s, "ValGlobal1", (m["Global1"]))
+	SetValueUsingPath(s, "ValCommand1Flag2", (m["Command1.Command1Flag2"]))
 }
 
 func TestCopyable(t *testing.T) {

parse.go

@@ -38,5 +38,9 @@ func (s *Settings[C]) Parse(args []string) *Settings[C] {
 
 	s.command.parse(r)
 
+	if s.mapping != nil && s.proxy != nil {
+		s.proxy.Copy(s.mapping)
+	}
+
 	return s
 }

pathfind.go

@@ -4,13 +4,14 @@
 package xflags
 
 import (
+	"fmt"
 	"reflect"
 	"strconv"
 	"strings"
 )
 
 // This function returns the value of a field in a struct, given a path to the field.
-func getValueFrom[D any](obj D, keyWithDots string) (interface{}, error) {
+func GetValueFrom[D any](obj D, keyWithDots string) (any, error) {
 	keySlice := strings.Split(keyWithDots, ".")
 	v := reflect.ValueOf(obj)
 
@@ -49,7 +50,7 @@ func getValueFrom[D any](obj D, keyWithDots string) (interface{}, error) {
 }
 
 // This function sets the value of a field in a struct, given a path to the field.
-func setValueUsingPath[D any](obj D, keyWithDots string, newValue string) error {
+func SetValueUsingPath[D any](obj D, keyWithDots string, newValue any) error {
 
 	keySlice := strings.Split(keyWithDots, ".")
 	v := reflect.ValueOf(obj)
@@ -94,29 +95,83 @@ func setValueUsingPath[D any](obj D, keyWithDots string, newValue string) error
 		return newCannotSetError(keyWithDots)
 	}
 
+	switch v.Kind() {
+	case reflect.Ptr:
+		if newValue == nil {
+			v.Set(reflect.Zero(v.Type()))
+		} else {
+			v.Set(reflect.ValueOf(&newValue))
+		}
+		return nil
+	}
+
+	newValueType := reflect.TypeOf(newValue)
+	if newValueType == nil {
+		return newUnsupportedTypePathError(keyWithDots, v.Type())
+	}
+
+	newValueKind := reflect.TypeOf(newValue).Kind()
+
 	switch v.Kind() {
 	case reflect.String:
-		v.SetString(newValue)
-	case reflect.Int:
+		if newValueKind == reflect.String {
+			v.SetString(newValue.(string))
+		} else {
+			v.SetString(fmt.Sprintf("%v", newValue))
+		}
+
+	case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int:
+
+		if newValueKind == reflect.Int {
+			v.SetInt(int64(newValue.(int)))
+		} else {
+			s, err := strconv.ParseInt(newValue.(string), 10, 64)
+			if err != nil {
+				return err
+			}
+			v.SetInt(s)
+		}
 
-		s, err := strconv.Atoi(newValue)
+	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+
+		if newValueKind == reflect.Int {
+			v.SetUint(uint64(newValue.(int)))
+		} else {
+			s, err := strconv.ParseInt(newValue.(string), 10, 64)
 			if err != nil {
 				return err
 			}
+			v.SetUint(uint64(s))
+		}
 
-		v.SetInt(int64(s))
 	case reflect.Bool:
-		v.SetBool(newValue == "true")
-	case reflect.Float64:
 
-		s, err := strconv.ParseFloat(newValue, 64)
+		if newValueKind == reflect.Bool {
+			v.SetBool(newValue.(bool))
+		} else {
+			b, err := strconv.ParseBool(newValue.(string))
+			if err != nil {
+				return err
+			}
+
+			v.SetBool(b)
+		}
+
+	case reflect.Float64, reflect.Float32:
+
+		if newValueKind == reflect.Float64 {
+			v.SetFloat(newValue.(float64))
+		} else {
+			s, err := strconv.ParseFloat(newValue.(string), 64)
 			if err != nil {
 				return err
 			}
 
 			v.SetFloat(s)
+		}
+
 	default:
-		return newUnsupportedTypeAtTopOfPathError(keyWithDots, v.Type())
+		return newInvalidTypeForPathError(keyWithDots, v.Type().String(), newValueKind.String())
 	}
 
 	return nil

pathfind_test.go

@@ -32,7 +32,7 @@ func TestPathFindError(t *testing.T) {
 
 	s := PathfindTestStruct1{}
 
-	_, err := getValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.XX")
+	_, err := GetValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.XX")
 	if err == nil {
 		t.Error("err == nil")
 	}
@@ -58,7 +58,7 @@ func TestPathFindSetValueString(t *testing.T) {
 
 	for k, v := range testData {
 		s := &PathfindTestStruct1{}
-		err := setValueUsingPath[*PathfindTestStruct1](s, k, v)
+		err := SetValueUsingPath[*PathfindTestStruct1](s, k, v)
 		if err != nil {
 			t.Error(err)
 		}
@@ -74,7 +74,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 	s.Sub1.Bs = "3"
 	s.Sub1.Bf = 4.0
 
-	v, err := getValueFrom[PathfindTestStruct1](s, "Sub1.B")
+	v, err := GetValueFrom[PathfindTestStruct1](s, "Sub1.B")
 	if err != nil {
 		t.Error(err)
 	}
@@ -83,7 +83,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 		t.Error("v != true")
 	}
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Bi")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Bi")
 	if err != nil {
 		t.Error(err)
 	}
@@ -92,7 +92,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 		t.Error("v != 2")
 	}
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Bs")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Bs")
 	if err != nil {
 		t.Error(err)
 	}
@@ -101,7 +101,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 		t.Error("v != 3")
 	}
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Bf")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Bf")
 	if err != nil {
 		t.Error(err)
 	}
@@ -115,7 +115,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 	s.Sub1.Sub2.Cs = "3"
 	s.Sub1.Sub2.Cf = 4.0
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.C")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.C")
 	if err != nil {
 		t.Error(err)
 	}
@@ -124,7 +124,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 		t.Error("v != true")
 	}
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Ci")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Ci")
 	if err != nil {
 		t.Error(err)
 	}
@@ -133,7 +133,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 		t.Error("v != 2")
 	}
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Cs")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Cs")
 	if err != nil {
 		t.Error(err)
 	}
@@ -142,7 +142,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 		t.Error("v != 3")
 	}
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Cf")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Cf")
 	if err != nil {
 		t.Error(err)
 	}
@@ -156,7 +156,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 	s.Sub1.Sub2.Sub3.Ds = "3"
 	s.Sub1.Sub2.Sub3.Df = 4.0
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.D")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.D")
 	if err != nil {
 		t.Error(err)
 
@@ -166,7 +166,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 		t.Error("v != true")
 	}
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Di")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Di")
 	if err != nil {
 		t.Error(err)
 	}
@@ -175,7 +175,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 		t.Error("v != 2")
 	}
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Ds")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Ds")
 	if err != nil {
 		t.Error(err)
 	}
@@ -184,7 +184,7 @@ func TestPathFindGetValueFrom(t *testing.T) {
 		t.Error("v != 3")
 	}
 
-	v, err = getValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Df")
+	v, err = GetValueFrom[PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Df")
 	if err != nil {
 		t.Error(err)
 	}
@@ -198,10 +198,10 @@ func TestPathFindGetValueFrom(t *testing.T) {
 func TestPathFindSetValueFrom(t *testing.T) {
 	s := &PathfindTestStruct1{}
 
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.B", "true")
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Bi", "2")
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Bs", "3")
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Bf", "4.0")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.B", "true")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Bi", "2")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Bs", "3")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Bf", "4.0")
 
 	if s.Sub1.B != true {
 		t.Error("s.Sub1.B != true")
@@ -220,10 +220,10 @@ func TestPathFindSetValueFrom(t *testing.T) {
 		t.Error("s.Sub1.Bf != 4.0")
 	}
 
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.C", "true")
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Ci", "2")
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Cs", "3")
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Cf", "4.0")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.C", "true")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Ci", "2")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Cs", "3")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Cf", "4.0")
 
 	if s.Sub1.Sub2.C != true {
 		t.Error("s.Sub1.Sub2.C != true")
@@ -250,10 +250,10 @@ func TestPathFindSetValueFrom(t *testing.T) {
 
 	}
 
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Sub3.D", "true")
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Di", "2")
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Ds", "3")
-	setValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Df", "4.0")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Sub3.D", "true")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Di", "2")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Ds", "3")
+	SetValueUsingPath[*PathfindTestStruct1](s, "Sub1.Sub2.Sub3.Df", "4.0")
 
 	if s.Sub1.Sub2.Sub3.D != true {
 		t.Error("s.Sub1.Sub2.Sub3.D != true")

readme_test.go

@@ -25,6 +25,13 @@ func TestReadMeInit(t *testing.T) {
 	setting.Parse([]string{"-v", "serve", "-h", "localhost", "-p", "8080"})
 	setting.Execute()
 	assert.True(t, setting.definitions.Verbose)
+
+	if setting.HasErrors() {
+		for _, err := range setting.Errors() {
+			t.Log(err)
+		}
+	}
+
 	assert.False(t, setting.HasErrors())
 }
 

setting.go

@@ -17,6 +17,7 @@ type config struct {
 	errorHandling flag.ErrorHandling
 }
 
+// Settings[C] is the main struct for the xflags package.
 type Settings[C any] struct {
 	definitions C
 
@@ -29,7 +30,8 @@ type Settings[C any] struct {
 
 	config config
 
-	shadow      any
+	mapping     map[string]any
+	proxy       Proxy
 	wasExecuted bool
 
 	hint string

tags.go

@@ -15,7 +15,6 @@ const (
 	tagShort       = "short"
 	tagLong        = "long"
 	tagDescription = "description"
-	tagShadow      = "shadow"
 )
 
 func getTagMap(field reflect.StructField) (value map[string]string) {