[chaley]

Try:

{#gr_2read:'switch($, "Yes", "To Read", template("[[author_sort]]/[[series]]"))'}/{title} - {authors}

if the CC #gr_2read contains the word "Yes", the constant string "To Read" is returned. If the CC contains anything else (including nothing), the evaluation of the template is returned.

Note that the regexps used by switch are case sensitive, and that the string values of a bool column are Yes, No, and empty. IIRC, Yes and No are translatable, so if you are not running in English, check to see what the text says.

Starting in 0.7.48 (or maybe 47) you can avoid translation by using raw_field, with will return 'True', 'False', and 'None'.

program:
	strcat(
		switch(raw_field('#gr_2read'), 'True', 'To Read', template('[[author_sort]]/[[series]]')), 
		template('/{title} - {authors}')
	)