See: <a href="/doc/reference/classes/ucalc/expressiontokens-=-[tokens]/">ExpressionTokens = [Tokens]</a>, <a href="/doc/reference/classes/ucalc.item/regex-=-[string]/">Regex = [string]</a>, <a href="/doc/reference/classes/ucalc.item/regex/regex-string,-regexgrammar/">Regex(string, RegExGrammar)</a>, <a href="/doc/reference/classes/ucalc.tokens/bytype/">ByType</a>