fn parse_anchor_function_fallback(
context: &ParserContext<'_>,
additional_functions: AdditionalFunctions,
input: &mut Parser<'_>,
) -> Result<Box<GenericAnchorFunctionFallback<Leaf>>, ParseError>fn parse_anchor_function_fallback(
context: &ParserContext<'_>,
additional_functions: AdditionalFunctions,
input: &mut Parser<'_>,
) -> Result<Box<GenericAnchorFunctionFallback<Leaf>>, ParseError>