can set error icon

confirm.go

@@ -86,7 +86,7 @@ func (c *Confirm) getBool(showHelp bool, config *PromptConfig) (bool, error) {
 			continue
 		default:
 			// we didnt get a valid answer, so print error and prompt again
-			if err := c.Error(fmt.Errorf("%q is not a valid answer, please try again.", val)); err != nil {
+			if err := c.Error(fmt.Errorf("%q is not a valid answer, please try again.", val), config.IconSet.Error); err != nil {
 				return c.Default, err
 			}
 			err := c.Render(

core/renderer.go

@@ -13,7 +13,12 @@ type Renderer struct {
 	errorLineCount int
 }
 
-var ErrorTemplate = `{{color "red"}}X Sorry, your reply was invalid: {{.Error}}{{color "reset"}}
+type ErrorTemplateData struct {
+	Error error
+	Icon  string
+}
+
+var ErrorTemplate = `{{color "red"}}{{ .Icon }} Sorry, your reply was invalid: {{ .Error.Error }}{{color "reset"}}
 `
 
 func (r *Renderer) WithStdio(stdio terminal.Stdio) {
@@ -35,14 +40,17 @@ func (r *Renderer) NewCursor() *terminal.Cursor {
 	}
 }
 
-func (r *Renderer) Error(invalid error) error {
+func (r *Renderer) Error(invalid error, icon string) error {
 	// since errors are printed on top we need to reset the prompt
 	// as well as any previous error print
 	r.resetPrompt(r.lineCount + r.errorLineCount)
 
 	// we just cleared the prompt lines
 	r.lineCount = 0
-	out, err := RunTemplate(ErrorTemplate, invalid)
+	out, err := RunTemplate(ErrorTemplate, &ErrorTemplateData{
+		Error: invalid,
+		Icon:  icon,
+	})
 	if err != nil {
 		return err
 	}

survey.go

@@ -55,7 +55,7 @@ type PromptConfig struct {
 type Prompt interface {
 	Prompt(config *PromptConfig) (interface{}, error)
 	Cleanup(interface{}, *PromptConfig) error
-	Error(error) error
+	Error(error, string) error
 }
 
 // PromptAgainer Interface for Prompts that support prompting again after invalid input
@@ -198,7 +198,7 @@ func Ask(qs []*Question, response interface{}, opts ...AskOpt) error {
 		if q.Validate != nil {
 			// wait for a valid response
 			for invalid := q.Validate(ans); invalid != nil; invalid = q.Validate(ans) {
-				err := q.Prompt.Error(invalid)
+				err := q.Prompt.Error(invalid, options.PromptConfig.IconSet.Error)
 				// if there was a problem
 				if err != nil {
 					return err

survey_test.go

@@ -231,7 +231,10 @@ func TestValidationError(t *testing.T) {
 
 	actual, err := core.RunTemplate(
 		core.ErrorTemplate,
-		err,
+		&core.ErrorTemplateData{
+			Error: err,
+			Icon:  "X",
+		},
 	)
 	if err != nil {
 		t.Errorf("Failed to run template to format error: %s", err)