CLCS

Syntactic Interaction of Documentation Strings and Declarations

In a number of situations, a documentation string can appear amidst a series of declare expressions prior to a series of forms.

In that case, if a string S appears where a documentation string is permissible and is not followed by either a declare expression or a form then S is taken to be a form; otherwise, S is taken as a documentation string. The consequences are unspecified if more than one such documentation string is present.