Enum PluginSeam 

pub enum PluginSeam {
    PickerSource,
    MultibufferViewSource,
    CompletionSource,
    Grammar,
    Events,
    Modes,
    Config,
    Decorations,
    Media,
    Context,
    Theme,
    Signs,
    Keymap,
    Logging,
    PluginManager,
    ErrorParser,
    Help,
    Dashboard,
    ScannedExcerptSource,
    TransientSource,
    Language,
}

Which extension seam a plugin’s component implements — the WIT world it exports. Each seam is its own world (picker-source, events-plugin, …); a component implements one, and the manifest declares which so the plugin loader (lattice-plugin-loader) knows which spawn_* path to drive. An empty provides list is a lifecycle-only plugin (the base plugin world — init.rs, the no-op fixture), driven through instantiate_plugin + activate rather than a seam actor.

Wire form (manifest provides = [...] + [Display]) is the dashed WIT interface name: picker-source, completion-source, grammar, events, modes, config, decorations, context.

Variants

PickerSource

MultibufferViewSource

MV.1 — a plugin-contributed multibuffer VIEW: the guest owns the view’s identity, contents, order and status, and the host owns the buffer and the excerpt machinery. Distinct from ScannedExcerptSource, which supplies rows to a view someone else owns.

CompletionSource

Grammar

Events

Modes

Config

Decorations

Media

IM.6: inline media blocks (inline-media.md §7). A producer, like Decorations — the guest names files and lines, the host resolves sizes and builds the virtual rows.

Context

TC.2 — the sticky-context producer (context-plugin world). Async, host-cached per parse version; see treesitter-context.md.

Theme

TC.4 — theme-element declaration (theme-plugin world). The plugin’s elements land in the SAME registry builtins use.

Signs

SG.3a — sign declaration (sign-plugin world). The plugin’s signs land in the SAME registry native producers use, styled through the ordinary theme registry.

Keymap

Logging

The wasi:logging-shaped guest→host logging import (PO.5, Layer 2). Not a native trait seam — the guest’s own narrative, host-captured into the same tracer as the boundary trace.

PluginManager

PM.7 — the require seam (plugin-manager-plugin world). A config guest (the user’s init.rs) declares the plugins it wants; the host records the specs and the loader resolves/builds/loads them off-thread. Deliberately its own seam rather than folded into config: declaring software to install is a strictly larger authority than setting an option, and provides is where that difference is visible to a user reading the manifest.

ErrorParser

CM.6 — a compilation-output parser (error-parser-plugin world). Sync, fed one captured line at a time by the compilation reader.

Help

CR.3 — plugin-contributed :help pages (help-plugin world). The markdown ships inside the component and crosses once, at load; the topic then lives in the same registry the builtin docs do.

Dashboard

CR.4 — plugin-contributed launch-page sections (dashboard-plugin world). Sync, and unlike help the guest stays instantiated: a section is a function of a live DashboardCtx, not data.

ScannedExcerptSource

OM.A1 — a plugin-contributed producer of scanned excerpts: rows found by reading many files, globally ordered and grouped (scanned-excerpt-source-plugin world). Async, driven once per file of a project walk. The guest declares the file extensions it wants offered, which is what keeps a filetype out of the host’s walk.

OR.9 renamed this from AgendaSource. Its record — line, end-line, group, label, sort-key — is an excerpt plus an ordering plus a group header, and contains nothing about org, dates or TODOs. The agenda is its first consumer, not its definition; a project-TODO view or a tags view is the same shape and should not have to register as an “agenda source”. Renamed while org was still the only consumer, because a seam name is API and third-party plugins would have bound to it.

TransientSource

TR.2b — a plugin-contributed transient menu (transient-source-plugin world). Async and live: id() is called once at load to key the registry entry, build(ctx) per menu open, because a builder’s rows depend on where the user opened it from.

Language

LG.3c — a plugin-contributed language (language-plugin world). Data, like help: the grammar bytes and query sources cross once at load and the guest is dropped. The host compiles the grammar (~100 ms) and owns the parse loop forever after, so there is no guest call on any hot path.

Implementations

impl PluginSeam

pub fn drain_rank(self) -> u8

Where this seam sits in the loader’s drain order (OM.0). Lower drains first; the loader stable-sorts a plugin’s provides by this before draining, so the order a manifest happens to list its seams in cannot change what registers.

The ordering exists because seams have real registration dependencies, and the one that bites is modes on grammar: a mode-keymap-binding resolves its command against the CommandRegistry at registration, so a mode binding a chord to the plugin’s OWN grammar action needs that action already registered. Drain the other way round and the binding is skipped with a log — the plugin loads “successfully” and the user’s chord silently does nothing.

This used to be the plugin author’s problem. Both bundled multi-seam manifests carried a hand-written comment telling the next author to put grammar before modes, which made a load-bearing invariant depend on prose inside a guest-authored file. Sorting here makes it a property of the seam set instead.

The ranks, and why each is where it is:

rank	seams	reason
0	config, logging	the option surface: every value any later seam reads exists after this
1	theme	theme elements later seams may name — and org derives its per-keyword elements from an OPTION, so it must follow rank 0
2	language	a major mode may declare target-language; the language should exist first
3	grammar	registers commands into the CommandRegistry
4	modes	keymap bindings resolve command names — needs rank 3
5	keymap	user-layer bindings, same name resolution
6	everything else	producers and data seams with no registration dependency

Ties keep manifest order (the sort is stable), so an author’s intent is respected everywhere it cannot break anything.

OA.14d split config from theme. They shared rank 0, so org’s register-theme-elements reading org.todo-keywords worked only because org’s provides happened to list config first — a load-bearing invariant living in a guest-authored file again, which is the exact thing this function exists to end. It is also the seam boundary the awaited pre-plugin-loaded fires on: the loader publishes it once every rank-0 seam has drained, so a handler can set an option that rank 1 and up will read.

pub fn as_str(self) -> &'static str

The dashed wire / display name (matches the WIT interface).

Trait Implementations

impl Clone for PluginSeam

fn clone(&self) -> PluginSeam

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for PluginSeam

impl Debug for PluginSeam

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for PluginSeam

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for PluginSeam

impl FromStr for PluginSeam

type Err = ()

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl PartialEq for PluginSeam

fn eq(&self, other: &PluginSeam) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for PluginSeam