Function mail_of 

pub fn mail_of(
    mail: &MailIndex,
    threads: &Threads<'_>,
    project: &Project,
    tied: &BTreeSet<String>,
    by_hand: &BTreeSet<String>,
    gate: Option<&Gate>,
    admissions: &mut Admissions,
) -> Vec<(String, bool)>

The mail a project takes, as its page shows it and agents’ consent reads it (consent::Consent::of): by its routes on the sender and the subject, by a tie (tied: the messages’ addresses, by_hand those you tied yourself), then the rest of their conversations (threads). With gate, each as the Porch takes it: never what it sets aside, nor by its sender’s address or domain when nothing authenticates it; what you tied by hand, as you tied it; conversations followed through the messages let in only. Without, every message as it stands. Each message’s id, and whether its sender is proven (always, without a gate).