I'm assuming that the "use dylan" is there for similar reasons as to why you declare that a package uses :cl in common lisp: This way if you want to define your

I'm assuming that the "use dylan" is there for similar reasons as to why you declare that a package uses :cl in common lisp: This way if you want to define your own functions that replace those in the language (eg. a custom + function) then you can simply omit importing the dylan namespace and define those without worry of conflicts.