d2lang/d2 · error

expected "bold" to be true or false

Error message

expected "bold" to be true or false

What it means

D2's style-setting code parses the "bold" style value with strconv.ParseBool; non-boolean values return this error and the style is not applied. Only runs when s.Bold is non-nil.

Source

Thrown at d2graph/d2graph.go:444

			return errors.New(`expected "font-color" to be a valid named color ("orange"), a hex code ("#f0ff3a"), or a gradient ("linear-gradient(red, blue)")`)
		}
		s.FontColor.Value = value
	case "animated":
		if s.Animated == nil {
			break
		}
		_, err := strconv.ParseBool(value)
		if err != nil {
			return errors.New(`expected "animated" to be true or false`)
		}
		s.Animated.Value = value
	case "bold":
		if s.Bold == nil {
			break
		}
		_, err := strconv.ParseBool(value)
		if err != nil {
			return errors.New(`expected "bold" to be true or false`)
		}
		s.Bold.Value = value
	case "italic":
		if s.Italic == nil {
			break
		}
		_, err := strconv.ParseBool(value)
		if err != nil {
			return errors.New(`expected "italic" to be true or false`)
		}
		s.Italic.Value = value
	case "underline":
		if s.Underline == nil {
			break
		}
		_, err := strconv.ParseBool(value)
		if err != nil {
			return errors.New(`expected "underline" to be true or false`)

View on GitHub (pinned to 0d69dca6f5)

Solutions

  1. Change the value to "true" or "false" (e.g. `x.bold: true`).
  2. Use 1 or 0 as accepted boolean numerics.
  3. Remove the bold key to keep the default weight.
  4. Validate style maps with strconv.ParseBool before assignment.

Example fix

// before (D2)
x: my shape
x.bold: strong
// after
x: my shape
x.bold: true
Defensive patterns

Strategy: validation

Validate before calling

func validStyleBool(v string) bool {
	_, err := strconv.ParseBool(v)
	return err == nil
}
// before applying: if !validStyleBool(boldVal) { /* fix or reject */ }

Type guard

func isParseBoolValue(s string) bool {
	switch s {
	case "1", "t", "T", "TRUE", "true", "True", "0", "f", "F", "FALSE", "false", "False":
		return true
	}
	return false
}

Try / catch

if err := obj.SetStyle("bold", val); err != nil {
	if strings.Contains(err.Error(), `"bold" to be true or false`) {
		// fallback: default weight
		val = "false"
	}
}

Prevention

When it happens

Trigger: Setting style key "bold" to a value strconv.ParseBool rejects, e.g. `x.bold: yes`, `bold: on`, or `bold: strong`.

Common situations: Typing "yes"/"on"/"strong" for bold text, or YAML/JSON configs using language-specific truthy keywords that D2 does not accept.

Related errors


AI-assisted analysis of d2lang/d2@0d69dca6f5 (2026-08-31). Data as JSON: /api/errors/22a46fab54e0c6e1. Report an issue: GitHub.