alef 0.85.17

Opinionated polyglot binding generator for Rust libraries
Documentation 
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{% if error_codes %}
// nativeError pairs a native error message with its sentinel so callers can
// match with errors.Is while still reading the detail the native layer
// produced, such as observed durations, limits and counts.
type nativeError struct {
	sentinel error
	message  string
}

// Error returns the message reported by the native layer.
func (e *nativeError) Error() string { return e.message }

// Unwrap returns the sentinel error, so errors.Is and errors.As keep working.
func (e *nativeError) Unwrap() error { return e.sentinel }

{% endif %}
// lastError retrieves the last error from the FFI layer.
func lastError() error {
	code := int32(C.{{ last_error_code_fn }}())
	if code == 0 {
		return nil
	}
	var message string
	if ctx := C.{{ last_error_context_fn }}(); ctx != nil {
		message = C.GoString(ctx)
	}
{% if error_codes %}
	var sentinel error
	switch code {
{% for error_code in error_codes %}
	case {{ error_code.0 }}:
		sentinel = {{ error_code.1 }}
{% endfor %}
	}
	if sentinel != nil {
		if message == "" {
			return sentinel
		}
		return &nativeError{sentinel: sentinel, message: message}
	}
{% endif %}
	if message == "" {
		return fmt.Errorf("[%d] native error", code)
	}
	return fmt.Errorf("[%d] %s", code, message)
}