modify an association list by associating a value with a key
Major Section:  PROGRAMMING

(Put-assoc-equal name val alist) returns an alist that is the same as the list alist, except that the first pair in alist with a car of name is replaced by (cons name val), if there is one. If there is no such pair, then (cons name val) is added at the end.

The guard of (put-assoc-equal name val alist) requires that alist is an alistp.