// An ErrorCode describes a failure to parse a regular expression.
type ErrorCode string

const (
	// Unexpected error
	ErrInternalError ErrorCode = "regexp/syntax: internal error"

	// Parse errors
	ErrInvalidCharClass      ErrorCode = "invalid character class"
	ErrInvalidCharRange      ErrorCode = "invalid character class range"
	ErrInvalidEscape         ErrorCode = "invalid escape sequence"