kovidgoyal/kitty · error

No key specified after flag

Error message

No key specified after flag %s

What it means

ParseMap parses a map directive string; while consuming leading --flags it splits on the first space. If no space remains after the flag, there is no key spec left, so it errors naming the flag.

Solutions

1. Append the key spec and action after the flag: `--allow-fallback=none ctrl+a 1`
2. Verify the whole map line wasn't cut off by a missing space

Example fix

# before
map --allow-fallback=none
# after
map --allow-fallback=none ctrl+a 1

if !strings.Contains(val, " ") { return fmt.Errorf("map directive lacks key/action after flags: %q", val) }

When it happens

Trigger: A map value consisting only of flags, e.g. `--allow-fallback=none` with no trailing key/action, or ending in a flag with nothing after it.

Common situations: Truncated map lines after editing, or a flag consuming the rest of the line because the key/action was accidentally deleted.

Understand the failure class

Background: "missing required config value" errors: why libraries refuse to start when a configuration key is empty, unset, or blank — this error's family across 48 libraries.

Related errors

• Invalid allow-fallback value %#v, allowed values: shifted…
• No key specified after
• allow_fallback values must be a subset of shifted, ascii…
• Empty include paths not allowed
• Failed to parse map = %#v with error

AI-assisted analysis of kovidgoyal/kitty@6d5d0c4406 (2026-08-27). Data as JSON: /api/errors/501066c51988ac75. Report an issue: GitHub.

Appendix: source

Thrown at tools/config/utils.go:276

func validateAllowFallback(value string) error {
	if value == "" || value == "none" {
		return nil
	}
	for part := range strings.SplitSeq(value, ",") {
		part = strings.TrimSpace(part)
		if part != "shifted" && part != "ascii" {
			return fmt.Errorf("Invalid allow-fallback value %#v, allowed values: shifted, ascii, none", part)
		}
	}
	return nil
}

func ParseMap(val string) (*KeyAction, error) {
	allow_fallback := "shifted"
	for strings.HasPrefix(val, "--") {
		flag, rest, found := strings.Cut(val, " ")
		if !found {
			return nil, fmt.Errorf("No key specified after flag %s", flag)
		}
		rest = strings.TrimSpace(rest)
		if name, value, ok := strings.Cut(flag, "="); ok {
			// --flag=value form
			name = strings.ReplaceAll(name[2:], "-", "_")
			switch name {
			case "allow_fallback":
				if err := validateAllowFallback(value); err != nil {
					return nil, err
				}
				if value == "none" {
					allow_fallback = ""
				} else {
					allow_fallback = value
				}
			default:
				return nil, fmt.Errorf("Unknown map option: %s", flag)
			}

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