- bi-dot-atomprocedure
- bi-dot-atom-text-stringprocedure
A dot-separated run of atoms, such as "jane.doe", folded to one string with the dots kept as part of it. bi-dot-atom additionally allows surrounding comments and folding whitespace, the way dot-atom does in the original grammar; bi-dot-atom-text-string does not, the way dot-atom-text does not, and is used where the RFC calls for dot-atom-text directly (a message ID's left and right parts, for instance).