go-delve/delve · error

empty evaluation string

Error message

empty evaluation string

What it means

Error "empty evaluation string" thrown in go-delve/delve.

Source

Thrown at service/dap/server.go:4736

//	"Expressions within {} are interpolated."
func parseLogPoint(msg string) (bool, *logMessage, error) {
	// Note: All braces *must* come in pairs, even those within an
	// expression to be interpolated.
	// TODO(suzmue): support individual braces in string values in
	// eval expressions.
	var args []string

	var isArg bool
	var formatSlice, argSlice []rune
	braceCount := 0
	for _, r := range msg {
		if isArg {
			switch r {
			case '}':
				if braceCount--; braceCount == 0 {
					argStr := strings.TrimSpace(string(argSlice))
					if len(argStr) == 0 {
						return false, nil, errors.New("empty evaluation string")
					}
					args = append(args, argStr)
					formatSlice = append(formatSlice, '%', 's')
					isArg = false
					continue
				}
			case '{':
				braceCount += 1
			}
			argSlice = append(argSlice, r)
			continue
		}

		switch r {
		case '}':
			return false, nil, errors.New("invalid log point format, unexpected '}'")
		case '{':
			if braceCount++; braceCount == 1 {

View on GitHub (pinned to a23773e6c3)

When it happens

Trigger: Thrown at service/dap/server.go:4736 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of go-delve/delve@a23773e6c3 (2026-08-31). Data as JSON: /api/errors/bdff616da16e4d2c. Report an issue: GitHub.