A `Literal domain which is a string surrounded by brackets.
val atom : string ->(atom, [> Rresult.R.msg ])Stdlib.result
atom x returns a safe atom element. If x does not respect RFC 5322, it returns Error. It accepts any characters excepts controls, space and specials characters - for instance, brackets are not allowed.
val make : 'at->'a->(Emile.domain, [> Rresult.R.msg ])Stdlib.result
make kind v returns a safe domain. It can fail if an user-defined literal-domain (Literal_domain.extension), a literal domain or a domain don't follow standards: