Enum FrontOp 

pub enum FrontOp {
    Exit,
    OpenMailbox(String),
    ErrorHistory(Vec<String>),
    WhatKey,
    OpenSelected,
    Compose(ComposeKind),
    Resend,
    RawEdit,
    Attachments,
    Folders,
    Query,
    Notmuch,
    ChangeMailbox {
        read_only: bool,
    },
    CommandPrompt,
    TagPrefix,
    Sidebar(SidebarOp),
    PageMove(PageSpot),
    Help,
    Redraw,
}

The functions a session cannot carry out, because they are about the display rather than the mail: a menu to open, a screen to repaint, an editor to hand the terminal to. The session has done whatever checking it can (a mailbox with unsaved changes will not be left, an unconfigured query will not be prompted for) before handing one of these back, so a front end can act on it directly.

Variants

Exit

mutt’s x: leave without writing anything back.

OpenMailbox(String)

Open this mailbox spec (mutt’s next-unread-mailbox found it).

ErrorHistory(Vec<String>)

Put these lines on a screen of their own: the error history, oldest first.

WhatKey

Read keys and say what they are until Ctrl+G.

OpenSelected

Read the selected message, however messages are read.

Compose(ComposeKind)

Start a draft. The session asks for the recipients once the front end has settled $recall.

Resend

mutt’s resend-message: the selected message as a new draft.

RawEdit

mutt’s e: the selected message’s own bytes, in an editor.

Attachments

The attachment menu for the selected message.

Folders

The folder browser.

Query

$query_command, which is configured: ask for the terms.

Notmuch

notmuch, which is not disabled: ask for the query.

ChangeMailbox

Somewhere else to open; the open mailbox is ready to be left.

Fields

read_only: bool

CommandPrompt

The : command line.

TagPrefix

mutt’s ;: the next function applies to the tagged set. There are tagged messages, or this would have been a complaint.

Sidebar(SidebarOp)

The mailbox pane.

PageMove(PageSpot)

Move the cursor by where it sits on screen, which only the front end knows: mutt’s H, M and L.

Help

mutt’s help screen.

Redraw

mutt’s Ctrl+L: repaint.